diff --git a/SLICE10.md b/SLICE10.md
index 18050a9..ff49a47 100644
--- a/SLICE10.md
+++ b/SLICE10.md
@@ -6,19 +6,22 @@
 
 ## Status
 
-**PLANNED.** Implementation has not started. Begin only after SLICE8 and SLICE9
-are complete and accepted.
+**IN PROGRESS.** Phases 1–6 and Phase 8 manual acceptance are complete. Phase 7
+(documentation) is the only remaining phase.
 
 ## Goal
 
-When a kanban or matrix block uses `scope: children`, render a separate complete
-view for the root notebook and each descendant notebook that owns eligible
+When a kanban or matrix block uses `scope: children` with `group: notebook`,
+render a separate complete view for the root notebook and each descendant notebook that owns eligible
 cards. This keeps large notebook trees browsable without nesting subsections
 inside one board or matrix.
 
 ## Confirmed behavior
 
-- Multi-view rendering applies only to the literal `scope: children` keyword.
+- Multi-view rendering requires both the literal `scope: children` keyword and
+  `group: notebook`.
+- `scope: children` without `group: notebook` retains the current aggregated
+  single view.
 - `this-folder`, numeric depths (including very large values), and `scope: all`
   keep their current single aggregated view.
 - The root notebook gets its own view for cards it owns directly.
@@ -55,8 +58,8 @@ still appear if they have cards.
 
 ```text
 parse scope
-  children -> scopeDepth: Infinity + groupByNotebook: true
-  other    -> existing values       + groupByNotebook: false
+  children + group: notebook -> scopeDepth: Infinity + groupByNotebook: true
+  all other combinations       -> existing depth     + groupByNotebook: false
         |
         v
 resolve root notebook + ordered scoped folder metadata
@@ -98,144 +101,273 @@ The empty grouped case carries `groups: []` and renders one existing empty state
 
 ## Implementation plan
 
-### Phase 1 — Preserve the explicit scope intent
+### Phase 1 — Preserve the explicit grouping intent
 
-- [ ] Add `groupByNotebook: boolean` to `KanbanConfig` and `MatrixConfig` in
-      `src/Gtd/types.ts`.
-- [ ] In both parsers, set `scopeDepth = Infinity` and
-      `groupByNotebook = true` only for literal `scope: children`.
-- [ ] Default `groupByNotebook` to false.
-- [ ] Keep `this-folder`, numeric depth, invalid-value fallback, and `scope: all`
-      parsing unchanged.
-- [ ] When `scope: all` is selected, force or leave `groupByNotebook` false;
-      `scopeAll` remains the controlling flag.
-- [ ] Add parser tests proving `children` is distinguishable from numeric depth
-      and that every other scope form remains single-view.
+- [x] Add `groupByNotebook: boolean` to `KanbanConfig` and `MatrixConfig`
+      in `src/Gtd/types.ts`.
+- [x] Recognize `group: notebook` in both parsers.
+- [x] Set `scopeDepth = Infinity` for literal `scope: children`, preserving
+      its existing recursion behavior.
+- [x] Set `groupByNotebook = true` only when literal `scope: children` and
+      `group: notebook` appear together.
+- [x] Default `groupByNotebook` to false, including `scope: children` without
+      the grouping option.
+- [x] Keep `this-folder`, numeric depth, invalid-value fallback, and
+      `scope: all` parsing unchanged.
+- [x] Warn and remain non-grouped when `group: notebook` is combined with
+      another scope, or when `group:` has an unsupported value.
+- [x] Add parser tests covering the grouped combination and every non-grouped
+      scope form.
 
 A boolean is deliberately preferred over a broad scope-enum refactor: existing
-collectors still need `scopeDepth` and `scopeAll`, while this slice needs only one
-additional rendering decision.
+collectors still need `scopeDepth` and `scopeAll`, while this slice needs only
+one additional rendering decision.
+
+### Phase 1 completion record
+
+- Kanban and matrix configs now preserve explicit notebook-grouping intent
+  independently of recursive scope depth.
+- Existing `scope: children` dashboards remain aggregated unless they opt in
+  with `group: notebook`.
+- Focused validation: 4 suites and 104 tests passed.
+- Full validation: 14 suites and 205 tests passed.
+- TypeScript, whitespace, and prohibited-reference checks passed.
+- No manual Joplin test is required for this parser-only phase.
 
 ### Phase 2 — Ordered notebook metadata helper
 
-- [ ] Extend `folderScope.ts` or add a focused `folderTree.ts` helper that returns
+- [x] Extend `folderScope.ts` or add a focused `folderTree.ts` helper that returns
       scoped folder metadata rather than only IDs when grouping is requested.
-- [ ] Include `id`, `parentId`, display title, and full path for the resolved root
+- [x] Include `id`, `parentId`, display title, and full path for the resolved root
       and every descendant.
-- [ ] Build paths from the actual notebook tree, including ancestors above a
+- [x] Build paths from the actual notebook tree, including ancestors above a
       `notebook:`-selected root so headings remain unambiguous.
-- [ ] Order root first, then perform depth-first traversal with siblings sorted
+- [x] Order root first, then perform depth-first traversal with siblings sorted
       by case-insensitive title and folder ID tie-breaker.
-- [ ] Handle missing/empty titles with a stable documented fallback such as
+- [x] Handle missing/empty titles with a stable documented fallback such as
       `Untitled notebook` while retaining the folder ID tie-breaker.
-- [ ] Defend against malformed folder data (orphan parent references and cycles)
+- [x] Defend against malformed folder data (orphan parent references and cycles)
       without hanging; keep every reachable scoped folder at most once.
-- [ ] Leave `resolveScopedFolderIds` behavior intact for calendars, Gantt, and
+- [x] Leave `resolveScopedFolderIds` behavior intact for calendars, Gantt, and
       non-grouped views.
 
+### Phase 2 completion record
+
+- Added `folderTree.ts` with typed scoped-folder metadata: folder ID, parent ID,
+  display title, and full notebook path.
+- Ordering is deterministic root-first depth-first; siblings sort by
+  case-insensitive display title and then folder ID.
+- Notebook-selected roots retain real ancestor paths above the selected root.
+- Blank titles use `Untitled notebook`.
+- Missing roots return no metadata; orphan roots remain usable; visited guards
+  prevent cycles and duplicate traversal.
+- The legacy `resolveScopedFolderIds` implementation and output remain unchanged.
+- Focused validation: 4 suites and 52 tests passed.
+- Full validation: 15 suites and 214 tests passed.
+- TypeScript, whitespace, and prohibited-reference checks passed.
+- No manual Joplin test is required for this pure metadata phase.
+
 ### Phase 3 — Grouped collector contracts
 
-- [ ] Add shared notebook-view metadata types plus `KanbanLayout` and
+- [x] Add shared notebook-view metadata types plus `KanbanLayout` and
       `MatrixLayout` discriminated unions in `src/Gtd/types.ts` or collector-local
       result types where appropriate.
-- [ ] Refactor kanban collection so each eligible card is appended to the board
+- [x] Refactor kanban collection so each eligible card is appended to the board
       associated with the current scanned `folderId` when grouping is enabled.
-- [ ] Apply done-window filtering and sort each kanban group's columns using the
+- [x] Apply done-window filtering and sort each kanban group's columns using the
       existing logic.
-- [ ] Refactor matrix collection equivalently and sort each group's quadrants.
-- [ ] Attach malformed-block/item warnings to the owning notebook group.
-- [ ] Omit groups whose final `cardCount` is zero, including groups emptied by
+- [x] Refactor matrix collection equivalently and sort each group's quadrants.
+- [x] Attach malformed-block/item warnings to the owning notebook group.
+- [x] Omit groups whose final `cardCount` is zero, including groups emptied by
       done-window or eligibility filtering.
-- [ ] Retain the current aggregate path and result behavior when grouping is off.
-- [ ] Compute overall `scannedFolders`, `scannedNotes`, and `cardCount` once,
+- [x] Retain the current aggregate path and result behavior when grouping is off.
+- [x] Compute overall `scannedFolders`, `scannedNotes`, and `cardCount` once,
       without summing repeated scans or duplicating cards.
-- [ ] Ensure the host view note is excluded before group counts are finalized.
+- [x] Ensure the host view note is excluded before group counts are finalized.
+
+### Phase 3 completion record
+
+- Added shared notebook-view metadata plus discriminated single/notebook layouts
+  for kanban and matrix results. The existing top-level board remains a temporary
+  empty alias in grouped mode so later payload consumers could migrate cleanly
+  without duplicating cards. The alias was removed after the Phase 5 webview
+  migration.
+- Grouped collectors scan every scoped folder once, bucket cards by the folder
+  currently being scanned, apply existing filtering and sorting per group, and
+  preserve the aggregate collector path when grouping is disabled.
+- Empty groups are omitted after filtering. Item warnings remain with their
+  owning non-empty group; overall folder, note, and card totals count unique
+  scans/cards once.
+- Added exact-owner coverage for root/child/grandchild cards, mixed notes and
+  to-dos, host-note exclusion, empty groups, done-window removal, group-local
+  warnings, ordering, sorting, both matrix modes, and single-layout regressions.
+- Focused validation: 4 suites and 110 tests passed.
+- Full validation: 15 suites and 219 tests passed.
+- Production TypeScript/webpack build and `git diff --check` passed; the package
+  was created at `publish/com.victorwiebe.joplin.plugin.gtd-calendar.jpl`.
+- No manual Joplin test is required for this collector-contract phase; grouped
+  payload and visual acceptance remain in Phases 4–8.
 
 ### Phase 4 — Plugin payloads and warning ownership
 
-- [ ] Update `handleGetKanban` and `handleGetMatrix` in `src/index.ts` to return
+- [x] Update `handleGetKanban` and `handleGetMatrix` in `src/index.ts` to return
       the discriminated layout plus SLICE8 `pageSize`.
-- [ ] Keep config warnings, notebook-resolution warnings, config parse errors,
+- [x] Keep config warnings, notebook-resolution warnings, config parse errors,
       and `scope: all` soft-cap warnings at the overall block level.
-- [ ] Send item-level warnings inside their notebook group in grouped mode.
-- [ ] Preserve the current top-level warning array in single mode.
-- [ ] Return a structurally valid empty layout when the source note cannot be
+- [x] Send item-level warnings inside their notebook group in grouped mode.
+- [x] Preserve the current top-level warning array in single mode.
+- [x] Return a structurally valid empty layout when the source note cannot be
       resolved.
-- [ ] Keep overall statistics visible once per source block; optionally show a
+- [x] Keep overall statistics visible once per source block; optionally show a
       compact per-notebook card count in each generated heading, but do not add
       separate scan totals that could imply folders were scanned repeatedly.
 
+### Phase 4 completion record
+
+- Kanban and matrix handlers now send the collector's discriminated `layout`
+  together with normalized `pageSize`, one overall statistics object, and the
+  existing global configuration fields.
+- Missing-source responses use the requested single/notebook discriminator and
+  return a structurally valid empty layout, including matrix labels and scope
+  metadata.
+- Configuration, YAML parse, notebook-resolution, and soft-cap warnings remain
+  overall. Single-mode item warnings retain the top-level warning path; grouped
+  item warnings remain inside their exact-owner notebook group.
+- A temporary legacy `board` alias kept the single-view webview working during
+  this phase. It was removed in Phase 5 after the webview migrated to `layout`;
+  grouped mode never duplicated cards into an aggregate payload.
+- Added pure payload-boundary helpers and tests for all missing-source layouts
+  and the no-aggregate compatibility behavior.
+- Focused validation: 3 suites and 83 tests passed.
+- Full validation: 16 suites and 221 tests passed.
+- TypeScript with `--skipLibCheck`, `git diff --check`, and the production
+  webpack/JPL build passed. The current artifact is
+  `publish/com.victorwiebe.joplin.plugin.gtd-calendar.jpl`.
+- No manual Joplin test is required for this payload-only phase; rendering and
+  manual acceptance remain in Phases 5–8.
+
 ### Phase 5 — Webview component reuse
 
-- [ ] Separate the existing kanban wrapper concerns (overall title, errors,
+- [x] Separate the existing kanban wrapper concerns (overall title, errors,
       global warnings, stats) from rendering one kanban board component.
-- [ ] Do the same for one matrix component.
-- [ ] In single mode, render exactly one component with current markup and visual
+- [x] Do the same for one matrix component.
+- [x] In single mode, render exactly one component with current markup and visual
       behavior.
-- [ ] In grouped mode, iterate groups in payload order and render one full
+- [x] In grouped mode, iterate groups in payload order and render one full
       component per group beneath a notebook-path heading.
-- [ ] Render each group's item warnings adjacent to that group.
-- [ ] Reuse the SLICE8 incremental-list helper inside every component; closure
+- [x] Render each group's item warnings adjacent to that group.
+- [x] Reuse the SLICE8 incremental-list helper inside every component; closure
       state must not be shared between groups or buckets.
-- [ ] When `groups` is empty, render the existing empty board/matrix once rather
+- [x] When `groups` is empty, render the existing empty board/matrix once rather
       than showing a blank block.
-- [ ] Add only the spacing/heading CSS required to distinguish notebook views;
+- [x] Add only the spacing/heading CSS required to distinguish notebook views;
       preserve column and matrix layout styles.
 
+### Phase 5 completion record
+
+- Split kanban and matrix rendering into overall wrappers plus reusable
+  one-board/one-matrix component functions. Single layouts retain the existing
+  component markup and visual behavior.
+- Notebook layouts render every non-empty group in collector order beneath its
+  full notebook path, with item warnings adjacent to the owning view.
+- Every generated component calls the existing SLICE8 incremental-list helper
+  separately for each column/quadrant, giving every bucket independent closure
+  state and the configured `pageSize`.
+- Empty notebook layouts render one ordinary empty board or matrix, preserving
+  the established overall empty presentation.
+- Removed the temporary top-level `board` payload alias. The webview consumes
+  `layout` directly, retaining only a defensive fallback for stale payloads.
+- Added only shared notebook-view spacing and heading styles; existing board,
+  matrix, card, and batching styles remain unchanged.
+- Full validation: JavaScript syntax, TypeScript with `--skipLibCheck`,
+  `git diff --check`, 16 suites/220 tests, and the production webpack/JPL build
+  all passed. The current artifact is
+  `publish/com.victorwiebe.joplin.plugin.gtd-calendar.jpl`.
+- Browser-only interaction testing remains deliberately manual because the
+  repository has no DOM harness; Phase 6 records that boundary explicitly.
+
 ### Phase 6 — Automated tests
 
 #### Scope/parser tests
 
-- [ ] `children` sets infinite depth plus grouping.
-- [ ] Numeric depth remains non-grouped, including a numeric string.
-- [ ] `this-folder`, invalid scope, and omitted scope remain non-grouped.
-- [ ] `scope: all` remains non-grouped and retains notebook-conflict warnings.
+- [x] `children` sets infinite depth plus grouping.
+- [x] Numeric depth remains non-grouped, including a numeric string.
+- [x] `this-folder`, invalid scope, and omitted scope remain non-grouped.
+- [x] `scope: all` remains non-grouped and retains notebook-conflict warnings.
 
 #### Folder-tree tests
 
-- [ ] Root plus multiple children and grandchildren.
-- [ ] Deterministic depth-first order regardless of input folder order.
-- [ ] Case-insensitive sibling ordering and folder-ID tie-breaker.
-- [ ] Duplicate titles represented by unambiguous full paths.
-- [ ] A `notebook:`-selected child root with its ancestor path retained.
-- [ ] Empty titles, orphan parents, and cycle protection.
+- [x] Root plus multiple children and grandchildren.
+- [x] Deterministic depth-first order regardless of input folder order.
+- [x] Case-insensitive sibling ordering and folder-ID tie-breaker.
+- [x] Duplicate titles represented by unambiguous full paths.
+- [x] A `notebook:`-selected child root with its ancestor path retained.
+- [x] Empty titles, orphan parents, and cycle protection.
 
 #### Kanban collector tests
 
-- [ ] Root-owned and descendant-owned cards appear in separate exact-owner groups.
-- [ ] Every card appears once with no ancestor rollup.
-- [ ] Empty groups are omitted while non-empty grandchildren remain.
-- [ ] Done-window filtering can remove an otherwise non-empty group.
-- [ ] Per-group sorting and warnings are correct.
-- [ ] SLICE9 note and to-do cards group identically.
-- [ ] Aggregate stats and card totals are not double-counted.
-- [ ] Non-grouped scope results remain unchanged.
+- [x] Root-owned and descendant-owned cards appear in separate exact-owner groups.
+- [x] Every card appears once with no ancestor rollup.
+- [x] Empty groups are omitted while non-empty grandchildren remain.
+- [x] Done-window filtering can remove an otherwise non-empty group.
+- [x] Per-group sorting and warnings are correct.
+- [x] SLICE9 note and to-do cards group identically.
+- [x] Aggregate stats and card totals are not double-counted.
+- [x] Non-grouped scope results remain unchanged.
 
 #### Matrix collector tests
 
-- [ ] Repeat exact-owner, omission, sorting, warning, mixed-card, and total-count
+- [x] Repeat exact-owner, omission, sorting, warning, mixed-card, and total-count
       coverage for Skeleton and Eisenhower modes.
-- [ ] Confirm all four quadrants remain local to their owning notebook group.
-- [ ] Confirm non-grouped scope results remain unchanged.
+- [x] Confirm all four quadrants remain local to their owning notebook group.
+- [x] Confirm non-grouped scope results remain unchanged.
 
 #### Payload/rendering contracts
 
-- [ ] Test single and grouped payload construction at the thinnest practical
+- [x] Test single and grouped payload construction at the thinnest practical
       boundary without adding a new browser-test dependency solely for this slice.
-- [ ] If SLICE8 introduced reusable DOM tests, extend them to prove independent
+- [x] If SLICE8 introduced reusable DOM tests, extend them to prove independent
       visible counts across notebook components; otherwise cover this manually.
-- [ ] Run focused parser, folder-tree, kanban, and matrix tests.
-- [ ] Run the complete Jest suite and record suite/test totals.
-- [ ] Run `npm run dist` and record the produced `.jpl` path.
-- [ ] Run `git diff --check` and the prohibited-reference audit.
+- [x] Run focused parser, folder-tree, kanban, and matrix tests.
+- [x] Run the complete Jest suite and record suite/test totals.
+- [x] Run `npm run dist` and record the produced `.jpl` path.
+- [x] Run `git diff --check` and the prohibited-reference audit.
+
+### Phase 6 completion record
+
+- Parser coverage now explicitly locks literal `children` grouping, numeric and
+  default non-grouped scopes, invalid fallbacks, and `scope: all` notebook
+  conflict warnings for both kanban and matrix.
+- Existing folder-tree coverage proves root/descendant traversal, deterministic
+  ordering, duplicate and blank titles, selected-root ancestor paths, orphans,
+  cycles, and unchanged legacy ID-only scope behavior.
+- Collector coverage now includes exact ownership, no rollups, empty-group and
+  done-window omission, local sorting/warnings, mixed cards, unique totals, all
+  four local quadrants in both matrix modes, and single-layout regressions for
+  `this-folder`, numeric depth, recursive children, and `scope: all`.
+- Pure layout helpers cover valid empty single/grouped payload construction.
+  The repository still has no DOM harness, so independent click-state remains
+  an explicit Phase 8 manual acceptance check rather than a test-only browser
+  abstraction.
+- Focused validation: 5 suites and 121 tests passed.
+- Full validation: 16 suites and 230 tests passed.
+- JavaScript syntax, TypeScript with `--skipLibCheck`, `git diff --check`, and
+  the prohibited-reference audit passed.
+- `npm run dist` produced
+  `publish/com.victorwiebe.joplin.plugin.gtd-calendar.jpl` (163,328 bytes,
+  SHA-256 `cc5eddd2dcd74453e5ebd2c2fd4635cb34eb5996bf736efd54441931f2a54930`).
+  The five-file tar archive was inspected and contains the grouped notebook-view
+  runtime markers.
+- No manual Joplin acceptance was performed; that remains Phase 8.
 
 ### Phase 7 — Documentation
 
-- [ ] Update README.md to state that literal `scope: children` produces separate
-      notebook views for kanban and matrix blocks.
+- [ ] Update README.md to state that `scope: children` plus `group: notebook`
+      produces separate notebook views for kanban and matrix blocks.
 - [ ] Add a parent/child/grandchild example showing root ownership, omitted empty
       notebooks, full-path headings, and no rollups.
-- [ ] State that numeric depth and `scope: all` remain aggregated.
+- [ ] State that ungrouped `children`, numeric depth, and `scope: all` remain
+      aggregated.
 - [ ] Explain that every generated bucket has independent SLICE8 expansion state.
 - [ ] Explain that SLICE9 notes group by their owning notebook.
 - [ ] Update SPEC.md scope parsing, folder traversal, layout payloads, warning
@@ -249,26 +381,40 @@ Create a root notebook containing direct cards, multiple children, grandchildren
 duplicate child titles under different parents, empty notebooks, and more than
 one SLICE8 batch in at least two generated views. Include SLICE9 notes and to-dos.
 
-- [ ] Confirm root-owned cards render only in the root view.
-- [ ] Confirm every descendant card renders only in its owning notebook view.
-- [ ] Confirm empty notebooks are omitted but non-empty descendants still appear.
-- [ ] Confirm full paths distinguish duplicate titles.
-- [ ] Confirm view ordering is stable and matches the documented traversal.
-- [ ] Confirm both matrix modes create separate complete matrices.
-- [ ] Confirm per-group warnings appear with the correct notebook.
-- [ ] Confirm overall statistics equal the unique scanned/card totals.
-- [ ] Confirm independent `page-size` limits and "List more" state across groups,
+- [x] Confirm root-owned cards render only in the root view.
+- [x] Confirm every descendant card renders only in its owning notebook view.
+- [x] Confirm empty notebooks are omitted but non-empty descendants still appear.
+- [x] Confirm full paths distinguish duplicate titles.
+- [x] Confirm view ordering is stable and matches the documented traversal.
+- [x] Confirm both matrix modes create separate complete matrices.
+- [x] Confirm per-group warnings appear with the correct notebook.
+- [x] Confirm overall statistics equal the unique scanned/card totals.
+- [x] Confirm independent `page-size` limits and "List more" state across groups,
       buckets, and multiple source blocks.
-- [ ] Confirm reload resets all expanded buckets.
-- [ ] Confirm `this-folder`, numeric depths, and `scope: all` still render one
+- [x] Confirm reload resets all expanded buckets.
+- [x] Confirm `this-folder`, numeric depths, and `scope: all` still render one
       aggregated view.
-- [ ] Confirm notebook targeting plus `scope: children` roots grouping at the
+- [x] Confirm notebook targeting plus `scope: children` roots grouping at the
       resolved target and uses correct full paths.
-- [ ] Confirm sorting, styling, navigation, completion, recurrence, and note-card
+- [x] Confirm sorting, styling, navigation, completion, recurrence, and note-card
       behavior do not regress.
-- [ ] Record user sign-off here; do not mark manual acceptance complete before
+- [x] Record user sign-off here; do not mark manual acceptance complete before
       confirmation.
 
+### Phase 8 acceptance record
+
+- **PASSED — USER SIGN-OFF RECEIVED 2026-07-28.** The user confirmed that all
+  Phase 8 manual tests passed against the current production JPL.
+- Accepted workflows include exact root/descendant ownership, no rollups or
+  duplication, empty-group handling, full-path headings, deterministic order,
+  both matrix modes, warning/statistics ownership, independent batching across
+  groups and blocks, reload reset, notebook targeting, and all non-grouped scope
+  regressions.
+- Sorting, styling, navigation, completion, recurrence, mixed note/to-do cards,
+  hover/focus controls, and configured page sizes were also manually accepted.
+- This manual acceptance is recorded separately from Phase 6 automated
+  validation. Phase 7 documentation remains pending.
+
 ## Acceptance criteria
 
 SLICE10 is complete only when:
@@ -316,4 +462,4 @@ SLICE10 is complete only when:
 Implement after SLICE8 and SLICE9 are complete. Start by preserving
 `groupByNotebook` in parser tests, then build and test ordered folder metadata.
 Introduce discriminated collector layouts before changing the webview. Complete
-single-view regression tests before grouped manual acceptance.
\ No newline at end of file
+single-view regression tests before grouped manual acceptance.
diff --git a/TASKS.md b/TASKS.md
index bf4c6e6..888c667 100644
--- a/TASKS.md
+++ b/TASKS.md
@@ -122,57 +122,59 @@ Implementation order: SLICE8, then SLICE9, then SLICE10.
 
 ### Scope and folder grouping
 
-- [ ] Preserve whether normalized kanban and matrix configuration came from the
-      explicit `scope: children` keyword.
-- [ ] Keep numeric scope, `this-folder`, and `scope: all` semantics unchanged.
-- [ ] Add a shared folder-tree helper that returns notebook IDs, titles, paths,
+- [x] Preserve explicit `scope: children` plus `group: notebook` intent in
+      normalized kanban and matrix configuration.
+- [x] Keep numeric scope, `this-folder`, and `scope: all` semantics unchanged.
+- [x] Add a shared folder-tree helper that returns notebook IDs, titles, paths,
       and parent relationships in deterministic tree/path order.
-- [ ] Handle nested notebooks and duplicate notebook names correctly.
-- [ ] Create one result group for cards owned directly by the root notebook.
-- [ ] Create one result group for cards owned directly by each descendant
+- [x] Handle nested notebooks and duplicate notebook names correctly.
+- [x] Create one result group for cards owned directly by the root notebook.
+- [x] Create one result group for cards owned directly by each descendant
       notebook.
-- [ ] Ensure every in-scope card appears in exactly one notebook group.
-- [ ] Omit empty notebook groups.
-- [ ] Preserve one overall empty-state presentation when all groups are empty.
+- [x] Ensure every in-scope card appears in exactly one notebook group.
+- [x] Omit empty notebook groups.
+- [x] Preserve one overall empty-state presentation when all groups are empty.
 
 ### Payloads and rendering
 
-- [ ] Add named per-notebook kanban and matrix groups to collection result types.
-- [ ] Retain compatible single-view results for every scope except `children`.
-- [ ] Provide aggregate and per-view statistics without double-counting notes or
+- [x] Add named per-notebook kanban and matrix groups to collection result types.
+- [x] Retain compatible single-view results unless both `scope: children` and
+      `group: notebook` are selected.
+- [x] Provide aggregate and per-view statistics without double-counting notes or
       cards.
-- [ ] Preserve warnings at the appropriate overall or notebook-view level.
-- [ ] Update plugin-to-webview messages and handlers for grouped results.
-- [ ] Render a complete kanban or matrix component for every non-empty group.
-- [ ] Use the full notebook path as each view heading.
-- [ ] Give every generated view independent SLICE8 expansion state.
-- [ ] Apply the configured `page-size` independently within every view bucket.
-- [ ] Group SLICE9 note cards by owning notebook in the same way as to-do cards.
+- [x] Preserve warnings at the appropriate overall or notebook-view level.
+- [x] Update plugin-to-webview messages and handlers for grouped results.
+- [x] Render a complete kanban or matrix component for every non-empty group.
+- [x] Use the full notebook path as each view heading.
+- [x] Give every generated view independent SLICE8 expansion state.
+- [x] Apply the configured `page-size` independently within every view bucket.
+- [x] Group SLICE9 note cards by owning notebook in the same way as to-do cards.
 
 ### Tests
 
-- [ ] Test preservation of the explicit `children` scope token.
-- [ ] Test deterministic folder ordering, nested paths, duplicate names, and
+- [x] Test preservation of explicit `children` plus `group: notebook` intent.
+- [x] Test deterministic folder ordering, nested paths, duplicate names, and
       empty groups.
-- [ ] Test that kanban cards appear exactly once in their owning notebook group.
-- [ ] Test the same invariant in Skeleton and Eisenhower matrices.
-- [ ] Include both note and to-do cards in grouping tests.
-- [ ] Test aggregate statistics and warnings for double-counting regressions.
+- [x] Test that kanban cards appear exactly once in their owning notebook group.
+- [x] Test the same invariant in Skeleton and Eisenhower matrices.
+- [x] Include both note and to-do cards in grouping tests.
+- [x] Test aggregate statistics and warnings for double-counting regressions.
 - [ ] Test independent batching and "List more" state across generated views.
-- [ ] Test that numeric scope, `this-folder`, and `scope: all` still produce one
-      view with unchanged behavior.
+- [x] Test that ungrouped `children`, numeric scope, `this-folder`, and
+      `scope: all` still produce one view with unchanged behavior.
 
 ### Documentation and acceptance
 
-- [ ] Document `scope: children` multi-view behavior in README.md.
+- [ ] Document `scope: children` plus `group: notebook` multi-view behavior
+      in README.md.
 - [ ] Add a parent/child/grandchild notebook example to README.md or SPEC.md.
 - [ ] Update architecture and payload behavior in SPEC.md.
-- [x] Add the feature to CHANGELOG.md.
+- [ ] Add the feature to CHANGELOG.md.
 - [x] Run the full automated test suite and record command/results.
 - [x] Run the production package build and record command/artifact.
-- [ ] Manually verify a parent notebook containing multiple children and
+- [x] Manually verify a parent notebook containing multiple children and
       grandchildren in Joplin.
-- [ ] Confirm headings, ordering, empty-group handling, no duplication, sorting,
+- [x] Confirm headings, ordering, empty-group handling, no duplication, sorting,
       styling, navigation, warnings, and independent expansion.
 - [ ] Mark SLICE10 complete in `SLICE10.md` and this file.
 
@@ -180,10 +182,10 @@ Implementation order: SLICE8, then SLICE9, then SLICE10.
 
 - [ ] Run the complete automated suite after all three slices are integrated.
 - [ ] Build the final production `.jpl` and record its path and version.
-- [ ] Verify a dashboard containing kanban and both matrix modes together.
-- [ ] Verify more than 20 mixed note/to-do cards across multiple child notebooks.
-- [ ] Confirm reload resets every expanded list to its configured initial size.
-- [ ] Record manual Joplin acceptance without conflating it with automated checks.
+- [x] Verify a dashboard containing kanban and both matrix modes together.
+- [x] Verify more than 20 mixed note/to-do cards across multiple child notebooks.
+- [x] Confirm reload resets every expanded list to its configured initial size.
+- [x] Record manual Joplin acceptance without conflating it with automated checks.
 - [ ] Re-run the repository-wide prohibited-reference audit.
 - [ ] Ensure README.md, SPEC.md, CHANGELOG.md, TASKS.md, and SLICE8–10 reflect the
-      final implementation state.
\ No newline at end of file
+      final implementation state.
diff --git a/src/Gtd/collectKanban.ts b/src/Gtd/collectKanban.ts
index 666849c..c6e492e 100644
--- a/src/Gtd/collectKanban.ts
+++ b/src/Gtd/collectKanban.ts
@@ -3,12 +3,17 @@ import {
 	KanbanBoard,
 	KanbanCard,
 	KanbanConfig,
+	KanbanLayout,
+	NotebookKanbanGroup,
 } from "./types";
 import resolveScopedFolderIds from "./folderScope";
+import resolveScopedFolderMetadata from "./folderTree";
 import extractGtdBlock from "./gtdBlock";
 import buildKanbanCard from "./buildKanbanCard";
 
 export interface KanbanResult {
+	layout: KanbanLayout;
+	/** @deprecated Phase 4 moves payload consumers to layout. Single-view alias. */
 	board: KanbanBoard;
 	warnings: string[];
 	scannedFolders: number;
@@ -37,17 +42,29 @@ export default async function collectKanban(
 	const warnings: string[] = [];
 
 	const folders = await adapter.getFolders();
-	const folderIds = resolveScopedFolderIds(
-		folders,
-		kanbanFolderId,
-		config.scopeDepth,
-		config.scopeAll
-	);
+	const folderMetadata = config.groupByNotebook
+		? resolveScopedFolderMetadata(folders, kanbanFolderId)
+		: [];
+	const folderIds = config.groupByNotebook
+		? folderMetadata.map((folder) => folder.id)
+		: resolveScopedFolderIds(
+				folders,
+				kanbanFolderId,
+				config.scopeDepth,
+				config.scopeAll
+		  );
 
 	let scannedNotes = 0;
 	const backlog: KanbanCard[] = [];
 	const inProgress: KanbanCard[] = [];
 	const done: KanbanCard[] = [];
+	const grouped = new Map<string, { board: KanbanBoard; warnings: string[] }>();
+	for (const folder of folderMetadata) {
+		grouped.set(folder.id, {
+			board: { backlog: [], inProgress: [], done: [] },
+			warnings: [],
+		});
+	}
 
 	const doneCutoff =
 		config.doneWindow === Infinity
@@ -58,6 +75,8 @@ export default async function collectKanban(
 	// to-do inclusion mode, so bodies are required for every scanned note.
 
 	for (const folderId of folderIds) {
+		const target = grouped.get(folderId);
+		const targetBoard = target?.board || { backlog, inProgress, done };
 		const notes = await adapter.getNotesInFolder(folderId, true);
 		for (const note of notes) {
 			scannedNotes += 1;
@@ -72,9 +91,8 @@ export default async function collectKanban(
 			}
 
 			if (result.error) {
-				warnings.push(
-					`"${note.title}": gtd block problem — ${result.error}`
-				);
+				const warning = `"${note.title}": gtd block problem — ${result.error}`;
+				(target?.warnings || warnings).push(warning);
 			}
 
 			const tags = await adapter.getNoteTagTitles(note.id);
@@ -82,29 +100,62 @@ export default async function collectKanban(
 
 			// Bucketing — Done wins.
 			if (card.completed) {
-				if (card.completedTime >= doneCutoff) done.push(card);
+				if (card.completedTime >= doneCutoff) targetBoard.done.push(card);
 				// completed but outside the window: dropped from the board
 			} else if (tags.includes(config.inProgressTag)) {
-				inProgress.push(card);
+				targetBoard.inProgress.push(card);
 			} else {
-				backlog.push(card);
+				targetBoard.backlog.push(card);
 			}
 		}
 	}
 
-	sortColumn(backlog, config);
-	sortColumn(inProgress, config);
-	sortColumn(done, config);
+	const groups: NotebookKanbanGroup[] = [];
+	for (const folder of folderMetadata) {
+		const target = grouped.get(folder.id) as {
+			board: KanbanBoard;
+			warnings: string[];
+		};
+		sortBoard(target.board, config);
+		const cardCount = countBoard(target.board);
+		if (cardCount > 0) {
+			groups.push({
+				folderId: folder.id,
+				notebookPath: folder.notebookPath,
+				board: target.board,
+				cardCount,
+				warnings: target.warnings,
+			});
+		}
+	}
+	if (!config.groupByNotebook) sortBoard({ backlog, inProgress, done }, config);
+	const board = { backlog, inProgress, done };
+	const layout: KanbanLayout = config.groupByNotebook
+		? { kind: "notebooks", groups }
+		: { kind: "single", board };
+	const cardCount = config.groupByNotebook
+		? groups.reduce((sum, group) => sum + group.cardCount, 0)
+		: countBoard(board);
 
 	return {
-		board: { backlog, inProgress, done },
+		layout,
+		board,
 		warnings,
 		scannedFolders: folderIds.length,
 		scannedNotes,
-		cardCount: backlog.length + inProgress.length + done.length,
+		cardCount,
 	};
 }
 
+function sortBoard(board: KanbanBoard, config: KanbanConfig): void {
+	sortColumn(board.backlog, config);
+	sortColumn(board.inProgress, config);
+	sortColumn(board.done, config);
+}
+
+function countBoard(board: KanbanBoard): number {
+	return board.backlog.length + board.inProgress.length + board.done.length;
+}
 
 function sortColumn(cards: KanbanCard[], config: KanbanConfig): void {
 	const direction = config.sort === "desc" ? -1 : 1;
diff --git a/src/Gtd/collectMatrix.ts b/src/Gtd/collectMatrix.ts
index 3dba457..d33116e 100644
--- a/src/Gtd/collectMatrix.ts
+++ b/src/Gtd/collectMatrix.ts
@@ -3,12 +3,17 @@ import {
 	KanbanCard,
 	MatrixBoard,
 	MatrixConfig,
+	MatrixLayout,
+	NotebookMatrixGroup,
 } from "./types";
 import resolveScopedFolderIds from "./folderScope";
+import resolveScopedFolderMetadata from "./folderTree";
 import extractGtdBlock from "./gtdBlock";
 import buildKanbanCard from "./buildKanbanCard";
 
 export interface MatrixResult {
+	layout: MatrixLayout;
+	/** @deprecated Phase 4 moves payload consumers to layout. Single-view alias. */
 	board: MatrixBoard;
 	warnings: string[];
 	scannedFolders: number;
@@ -40,18 +45,30 @@ export default async function collectMatrix(
 	const warnings: string[] = [];
 
 	const folders = await adapter.getFolders();
-	const folderIds = resolveScopedFolderIds(
-		folders,
-		matrixFolderId,
-		config.scopeDepth,
-		config.scopeAll
-	);
+	const folderMetadata = config.groupByNotebook
+		? resolveScopedFolderMetadata(folders, matrixFolderId)
+		: [];
+	const folderIds = config.groupByNotebook
+		? folderMetadata.map((folder) => folder.id)
+		: resolveScopedFolderIds(
+				folders,
+				matrixFolderId,
+				config.scopeDepth,
+				config.scopeAll
+		  );
 
 	let scannedNotes = 0;
 	const topLeft: KanbanCard[] = [];
 	const topRight: KanbanCard[] = [];
 	const bottomLeft: KanbanCard[] = [];
 	const bottomRight: KanbanCard[] = [];
+	const grouped = new Map<string, { board: MatrixBoard; warnings: string[] }>();
+	for (const folder of folderMetadata) {
+		grouped.set(folder.id, {
+			board: { topLeft: [], topRight: [], bottomLeft: [], bottomRight: [] },
+			warnings: [],
+		});
+	}
 
 	// Skeleton mode: a date on or before this ISO threshold is "due soon".
 	const soonThreshold = isoDaysFromNow(now, config.urgentWindow);
@@ -60,6 +77,13 @@ export default async function collectMatrix(
 	// to-do inclusion mode, so bodies are required for every scanned note.
 
 	for (const folderId of folderIds) {
+		const target = grouped.get(folderId);
+		const targetBoard = target?.board || {
+			topLeft,
+			topRight,
+			bottomLeft,
+			bottomRight,
+		};
 		const notes = await adapter.getNotesInFolder(folderId, true);
 		for (const note of notes) {
 			scannedNotes += 1;
@@ -75,9 +99,8 @@ export default async function collectMatrix(
 			}
 
 			if (result.error) {
-				warnings.push(
-					`"${note.title}": gtd block problem — ${result.error}`
-				);
+				const warning = `"${note.title}": gtd block problem — ${result.error}`;
+				(target?.warnings || warnings).push(warning);
 			}
 
 			const tags = await adapter.getNoteTagTitles(note.id);
@@ -100,31 +123,68 @@ export default async function collectMatrix(
 					(card.date !== null && card.date <= soonThreshold);
 			}
 
-			if (topRow && leftColumn) topLeft.push(card);
-			else if (topRow) topRight.push(card);
-			else if (leftColumn) bottomLeft.push(card);
-			else bottomRight.push(card);
+			if (topRow && leftColumn) targetBoard.topLeft.push(card);
+			else if (topRow) targetBoard.topRight.push(card);
+			else if (leftColumn) targetBoard.bottomLeft.push(card);
+			else targetBoard.bottomRight.push(card);
 		}
 	}
 
-	sortColumn(topLeft, config);
-	sortColumn(topRight, config);
-	sortColumn(bottomLeft, config);
-	sortColumn(bottomRight, config);
+	const groups: NotebookMatrixGroup[] = [];
+	for (const folder of folderMetadata) {
+		const target = grouped.get(folder.id) as {
+			board: MatrixBoard;
+			warnings: string[];
+		};
+		sortBoard(target.board, config);
+		const cardCount = countBoard(target.board);
+		if (cardCount > 0) {
+			groups.push({
+				folderId: folder.id,
+				notebookPath: folder.notebookPath,
+				board: target.board,
+				cardCount,
+				warnings: target.warnings,
+			});
+		}
+	}
+	if (!config.groupByNotebook) {
+		sortBoard({ topLeft, topRight, bottomLeft, bottomRight }, config);
+	}
+	const board = { topLeft, topRight, bottomLeft, bottomRight };
+	const layout: MatrixLayout = config.groupByNotebook
+		? { kind: "notebooks", groups }
+		: { kind: "single", board };
+	const cardCount = config.groupByNotebook
+		? groups.reduce((sum, group) => sum + group.cardCount, 0)
+		: countBoard(board);
 
 	return {
-		board: { topLeft, topRight, bottomLeft, bottomRight },
+		layout,
+		board,
 		warnings,
 		scannedFolders: folderIds.length,
 		scannedNotes,
-		cardCount:
-			topLeft.length +
-			topRight.length +
-			bottomLeft.length +
-			bottomRight.length,
+		cardCount,
 	};
 }
 
+function sortBoard(board: MatrixBoard, config: MatrixConfig): void {
+	sortColumn(board.topLeft, config);
+	sortColumn(board.topRight, config);
+	sortColumn(board.bottomLeft, config);
+	sortColumn(board.bottomRight, config);
+}
+
+function countBoard(board: MatrixBoard): number {
+	return (
+		board.topLeft.length +
+		board.topRight.length +
+		board.bottomLeft.length +
+		board.bottomRight.length
+	);
+}
+
 /** ISO yyyy-mm-dd for local `now` plus `days`. */
 function isoDaysFromNow(now: Date, days: number): string {
 	const d = new Date(now.getFullYear(), now.getMonth(), now.getDate() + days);
@@ -137,7 +197,6 @@ function isoDaysFromNow(now: Date, days: number): string {
 	);
 }
 
-
 function sortColumn(cards: KanbanCard[], config: MatrixConfig): void {
 	const direction = config.sort === "desc" ? -1 : 1;
 
diff --git a/src/Gtd/folderTree.ts b/src/Gtd/folderTree.ts
new file mode 100644
index 0000000..2d0f006
--- /dev/null
+++ b/src/Gtd/folderTree.ts
@@ -0,0 +1,93 @@
+import { RawFolder } from "./types";
+
+export const UNTITLED_NOTEBOOK = "Untitled notebook";
+
+export interface ScopedFolderMetadata {
+	id: string;
+	parentId: string;
+	title: string;
+	notebookPath: string;
+}
+
+/**
+ * Return the selected root and every reachable descendant in deterministic
+ * depth-first order. Paths retain ancestors above a notebook-selected root.
+ */
+export default function resolveScopedFolderMetadata(
+	folders: RawFolder[],
+	rootFolderId: string
+): ScopedFolderMetadata[] {
+	const foldersById = new Map<string, RawFolder>();
+	for (const folder of folders) {
+		if (!foldersById.has(folder.id)) foldersById.set(folder.id, folder);
+	}
+
+	const root = foldersById.get(rootFolderId);
+	if (!root) return [];
+
+	const childrenByParent = new Map<string, RawFolder[]>();
+	for (const folder of foldersById.values()) {
+		const siblings = childrenByParent.get(folder.parent_id) || [];
+		siblings.push(folder);
+		childrenByParent.set(folder.parent_id, siblings);
+	}
+	for (const siblings of childrenByParent.values()) {
+		siblings.sort(compareFolders);
+	}
+
+	const result: ScopedFolderMetadata[] = [];
+	const visited = new Set<string>();
+	const stack: RawFolder[] = [root];
+
+	while (stack.length > 0) {
+		const folder = stack.pop() as RawFolder;
+		if (visited.has(folder.id)) continue;
+		visited.add(folder.id);
+
+		result.push({
+			id: folder.id,
+			parentId: folder.parent_id,
+			title: displayTitle(folder),
+			notebookPath: buildNotebookPath(folder, foldersById),
+		});
+
+		const children = childrenByParent.get(folder.id) || [];
+		for (let i = children.length - 1; i >= 0; i -= 1) {
+			if (!visited.has(children[i].id)) stack.push(children[i]);
+		}
+	}
+
+	return result;
+}
+
+function displayTitle(folder: RawFolder): string {
+	const title = (folder.title || "").trim();
+	return title || UNTITLED_NOTEBOOK;
+}
+
+function compareFolders(a: RawFolder, b: RawFolder): number {
+	const aTitle = displayTitle(a).toLowerCase();
+	const bTitle = displayTitle(b).toLowerCase();
+	if (aTitle < bTitle) return -1;
+	if (aTitle > bTitle) return 1;
+	if (a.id < b.id) return -1;
+	if (a.id > b.id) return 1;
+	return 0;
+}
+
+function buildNotebookPath(
+	folder: RawFolder,
+	foldersById: Map<string, RawFolder>
+): string {
+	const segments: string[] = [];
+	const visited = new Set<string>();
+	let current: RawFolder | undefined = folder;
+
+	while (current && !visited.has(current.id)) {
+		visited.add(current.id);
+		segments.unshift(displayTitle(current));
+		current = foldersById.get(current.parent_id);
+	}
+
+	return segments.join("/");
+}
\ No newline at end of file
diff --git a/src/Gtd/layoutPayload.ts b/src/Gtd/layoutPayload.ts
new file mode 100644
index 0000000..3b75366
--- /dev/null
+++ b/src/Gtd/layoutPayload.ts
@@ -0,0 +1,19 @@
+import { KanbanBoard, KanbanLayout, MatrixBoard, MatrixLayout } from "./types";
+
+export function emptyKanbanBoard(): KanbanBoard {
+	return { backlog: [], inProgress: [], done: [] };
+}
+
+export function emptyMatrixBoard(): MatrixBoard {
+	return { topLeft: [], topRight: [], bottomLeft: [], bottomRight: [] };
+}
+
+export function emptyKanbanLayout(groupByNotebook: boolean): KanbanLayout {
+	if (groupByNotebook) return { kind: "notebooks", groups: [] };
+	return { kind: "single", board: emptyKanbanBoard() };
+}
+
+export function emptyMatrixLayout(groupByNotebook: boolean): MatrixLayout {
+	if (groupByNotebook) return { kind: "notebooks", groups: [] };
+	return { kind: "single", board: emptyMatrixBoard() };
+}
diff --git a/src/Gtd/parseKanbanConfig.ts b/src/Gtd/parseKanbanConfig.ts
index e6f1ee3..c7bc36e 100644
--- a/src/Gtd/parseKanbanConfig.ts
+++ b/src/Gtd/parseKanbanConfig.ts
@@ -17,6 +17,7 @@ export default function parseKanbanConfig(raw: any): KanbanConfig {
 	const knownKeys = [
 		"title",
 		"scope",
+		"group",
 		"notebook",
 		"todos",
 		"sort-type",
@@ -38,6 +39,7 @@ export default function parseKanbanConfig(raw: any): KanbanConfig {
 	// scope (shared semantics with gtd-calendar)
 	let scopeDepth = 0;
 	let scopeAll = false;
+	let childrenScope = false;
 	if (input.scope !== undefined) {
 		const value = input.scope;
 		if (value === "all") {
@@ -46,6 +48,7 @@ export default function parseKanbanConfig(raw: any): KanbanConfig {
 			scopeDepth = 0;
 		} else if (value === "children") {
 			scopeDepth = Infinity;
+			childrenScope = true;
 		} else if (Number.isInteger(Number(value)) && Number(value) >= 0) {
 			scopeDepth = Number(value);
 		} else {
@@ -53,6 +56,22 @@ export default function parseKanbanConfig(raw: any): KanbanConfig {
 		}
 	}
 
+	let groupByNotebook = false;
+	if (input.group !== undefined) {
+		const candidate = String(input.group).trim().toLowerCase();
+		if (candidate !== "notebook") {
+			warnings.push(
+				`Invalid group "${input.group}" (grouping disabled)`
+			);
+		} else if (!childrenScope) {
+			warnings.push(
+				'"group: notebook" requires scope: children (grouping disabled)'
+			);
+		} else {
+			groupByNotebook = true;
+		}
+	}
+
 	const notebook = parseNotebookOption(input.notebook);
 	if (scopeAll && notebook) {
 		warnings.push(
@@ -138,6 +157,7 @@ export default function parseKanbanConfig(raw: any): KanbanConfig {
 		title,
 		scopeDepth,
 		scopeAll,
+		groupByNotebook,
 		notebook,
 		todos,
 		sortType,
diff --git a/src/Gtd/parseMatrixConfig.ts b/src/Gtd/parseMatrixConfig.ts
index 4f211c4..0696d54 100644
--- a/src/Gtd/parseMatrixConfig.ts
+++ b/src/Gtd/parseMatrixConfig.ts
@@ -26,6 +26,7 @@ export default function parseMatrixConfig(raw: any): MatrixConfig {
 		"mode",
 		"title",
 		"scope",
+		"group",
 		"notebook",
 		"todos",
 		"sort-type",
@@ -60,6 +61,7 @@ export default function parseMatrixConfig(raw: any): MatrixConfig {
 	// scope (shared semantics with gtd-calendar / gtd-kanban)
 	let scopeDepth = 0;
 	let scopeAll = false;
+	let childrenScope = false;
 	if (input.scope !== undefined) {
 		const value = input.scope;
 		if (value === "all") {
@@ -68,6 +70,7 @@ export default function parseMatrixConfig(raw: any): MatrixConfig {
 			scopeDepth = 0;
 		} else if (value === "children") {
 			scopeDepth = Infinity;
+			childrenScope = true;
 		} else if (Number.isInteger(Number(value)) && Number(value) >= 0) {
 			scopeDepth = Number(value);
 		} else {
@@ -75,6 +78,22 @@ export default function parseMatrixConfig(raw: any): MatrixConfig {
 		}
 	}
 
+	let groupByNotebook = false;
+	if (input.group !== undefined) {
+		const candidate = String(input.group).trim().toLowerCase();
+		if (candidate !== "notebook") {
+			warnings.push(
+				`Invalid group "${input.group}" (grouping disabled)`
+			);
+		} else if (!childrenScope) {
+			warnings.push(
+				'"group: notebook" requires scope: children (grouping disabled)'
+			);
+		} else {
+			groupByNotebook = true;
+		}
+	}
+
 	const notebook = parseNotebookOption(input.notebook);
 	if (scopeAll && notebook) {
 		warnings.push(
@@ -160,6 +179,7 @@ export default function parseMatrixConfig(raw: any): MatrixConfig {
 		title,
 		scopeDepth,
 		scopeAll,
+		groupByNotebook,
 		notebook,
 		todos,
 		sortType,
diff --git a/src/Gtd/types.ts b/src/Gtd/types.ts
index 91eabe8..cc23305 100644
--- a/src/Gtd/types.ts
+++ b/src/Gtd/types.ts
@@ -98,10 +98,7 @@ export interface DataAdapter {
 	 * may omit the (potentially large) `body` field. Collectors pass false only
 	 * when their inclusion mode guarantees the gtd block is never scanned.
 	 */
-	getNotesInFolder(
-		folderId: string,
-		includeBody: boolean
-	): Promise<RawNote[]>;
+	getNotesInFolder(folderId: string, includeBody: boolean): Promise<RawNote[]>;
 	/** Lowercased tag titles for a note. Used to detect recurrence. */
 	getNoteTagTitles(noteId: string): Promise<string[]>;
 }
@@ -129,6 +126,8 @@ export interface KanbanConfig {
 	scopeDepth: number;
 	/** `scope: all` — scan every notebook; ignores scopeDepth and notebook. */
 	scopeAll: boolean;
+	/** Separate exact-owner notebook views; requires children + notebook grouping. */
+	groupByNotebook: boolean;
 	/** Notebook to root the scan at (id/title/path); null = host folder. */
 	notebook: string | null;
 	todos: InclusionMode;
@@ -165,6 +164,22 @@ export interface KanbanBoard {
 	done: KanbanCard[];
 }
 
+/** Identity shared by every exact-owner notebook view. */
+export interface NotebookViewMetadata {
+	folderId: string;
+	notebookPath: string;
+	cardCount: number;
+	warnings: string[];
+}
+
+export interface NotebookKanbanGroup extends NotebookViewMetadata {
+	board: KanbanBoard;
+}
+
+export type KanbanLayout =
+	| { kind: "single"; board: KanbanBoard }
+	| { kind: "notebooks"; groups: NotebookKanbanGroup[] };
+
 /**
  * Default tags for the Eisenhower matrix axes. Overridable via the
  * gtd-matrix `urgent-tag:` / `important-tag:` options.
@@ -181,6 +196,8 @@ export interface MatrixConfig {
 	scopeDepth: number;
 	/** `scope: all` — scan every notebook; ignores scopeDepth and notebook. */
 	scopeAll: boolean;
+	/** Separate exact-owner notebook views; requires children + notebook grouping. */
+	groupByNotebook: boolean;
 	/** Notebook to root the scan at (id/title/path); null = host folder. */
 	notebook: string | null;
 	todos: InclusionMode;
@@ -213,6 +230,14 @@ export interface MatrixBoard {
 	bottomRight: KanbanCard[];
 }
 
+export interface NotebookMatrixGroup extends NotebookViewMetadata {
+	board: MatrixBoard;
+}
+
+export type MatrixLayout =
+	| { kind: "single"; board: MatrixBoard }
+	| { kind: "notebooks"; groups: NotebookMatrixGroup[] };
+
 /** Display labels for a matrix mode, sent to the webview. */
 export interface MatrixLabels {
 	columns: [string, string];
diff --git a/src/event-calendar.css b/src/event-calendar.css
index 10a99dd..542f084 100644
--- a/src/event-calendar.css
+++ b/src/event-calendar.css
@@ -291,6 +291,18 @@
 	margin: 0.5em 0;
 }
 
+.gtd-notebook-view + .gtd-notebook-view {
+	margin-top: 1.25em;
+}
+
+.gtd-notebook-view-heading {
+	margin: 0 0 0.45em;
+	font-size: 1em;
+	font-weight: 600;
+	border-bottom: 1px solid rgba(128, 128, 128, 0.3);
+	padding-bottom: 0.25em;
+}
+
 .gtd-kanban-columns {
 	display: grid;
 	grid-template-columns: repeat(3, 1fr);
diff --git a/src/gtd-calendar-webview.js b/src/gtd-calendar-webview.js
index b6aa12b..67dbda0 100644
--- a/src/gtd-calendar-webview.js
+++ b/src/gtd-calendar-webview.js
@@ -492,14 +492,63 @@
 			wrapper.appendChild(warn);
 		});
 
-		const board = payload.board || {
+		const emptyBoard = {
 			backlog: [],
 			inProgress: [],
 			done: [],
 		};
+		const layout = payload.layout || {
+			kind: "single",
+			board: payload.board || emptyBoard,
+		};
 		const detail = payload.cardDetail || "hover";
 		const pageSize = payload.pageSize || 10;
 
+		if (layout.kind === "notebooks" && layout.groups.length > 0) {
+			layout.groups.forEach(function (group) {
+				wrapper.appendChild(
+					renderNotebookKanbanGroup(group, pageSize, detail, contentScriptId)
+				);
+			});
+		} else {
+			const board = layout.kind === "single" ? layout.board : emptyBoard;
+			wrapper.appendChild(
+				renderKanbanBoard(board, pageSize, detail, contentScriptId)
+			);
+		}
+
+		if (payload.stats) {
+			const meta = document.createElement("p");
+			meta.className = "gtd-calendar-debug-meta";
+			meta.textContent =
+				payload.stats.cardCount +
+				" card(s) from " +
+				payload.stats.scannedNotes +
+				" note(s) in " +
+				payload.stats.scannedFolders +
+				" folder(s)" +
+				(payload.scopeAll ? " · scope: all (every notebook)" : "");
+			wrapper.appendChild(meta);
+		}
+
+		el.appendChild(wrapper);
+	}
+
+	function renderNotebookKanbanGroup(group, pageSize, detail, contentScriptId) {
+		const section = document.createElement("section");
+		section.className = "gtd-notebook-view";
+		const heading = document.createElement("h4");
+		heading.className = "gtd-notebook-view-heading";
+		heading.textContent = group.notebookPath;
+		section.appendChild(heading);
+		renderViewWarnings(section, group.warnings);
+		section.appendChild(
+			renderKanbanBoard(group.board, pageSize, detail, contentScriptId)
+		);
+		return section;
+	}
+
+	function renderKanbanBoard(board, pageSize, detail, contentScriptId) {
 		const columns = document.createElement("div");
 		columns.className = "gtd-kanban-columns";
 
@@ -519,23 +568,7 @@
 			renderColumn("Done", board.done, pageSize, detail, contentScriptId)
 		);
 
-		wrapper.appendChild(columns);
-
-		if (payload.stats) {
-			const meta = document.createElement("p");
-			meta.className = "gtd-calendar-debug-meta";
-			meta.textContent =
-				payload.stats.cardCount +
-				" card(s) from " +
-				payload.stats.scannedNotes +
-				" note(s) in " +
-				payload.stats.scannedFolders +
-				" folder(s)" +
-				(payload.scopeAll ? " · scope: all (every notebook)" : "");
-			wrapper.appendChild(meta);
-		}
-
-		el.appendChild(wrapper);
+		return columns;
 	}
 
 	function renderColumn(title, cards, pageSize, detail, contentScriptId) {
@@ -710,12 +743,16 @@
 			wrapper.appendChild(warn);
 		});
 
-		const board = payload.board || {
+		const emptyBoard = {
 			topLeft: [],
 			topRight: [],
 			bottomLeft: [],
 			bottomRight: [],
 		};
+		const layout = payload.layout || {
+			kind: "single",
+			board: payload.board || emptyBoard,
+		};
 		const labels = payload.labels || {
 			columns: ["Urgent", "Not urgent"],
 			rows: ["Important", "Not important"],
@@ -729,6 +766,81 @@
 		const detail = payload.cardDetail || "hover";
 		const pageSize = payload.pageSize || 10;
 
+		if (layout.kind === "notebooks" && layout.groups.length > 0) {
+			layout.groups.forEach(function (group) {
+				wrapper.appendChild(
+					renderNotebookMatrixGroup(
+						group,
+						labels,
+						pageSize,
+						detail,
+						contentScriptId
+					)
+				);
+			});
+		} else {
+			const board = layout.kind === "single" ? layout.board : emptyBoard;
+			wrapper.appendChild(
+				renderMatrixBoard(
+					board,
+					labels,
+					pageSize,
+					detail,
+					contentScriptId
+				)
+			);
+		}
+
+		if (payload.stats) {
+			const meta = document.createElement("p");
+			meta.className = "gtd-calendar-debug-meta";
+			meta.textContent =
+				payload.stats.cardCount +
+				" card(s) from " +
+				payload.stats.scannedNotes +
+				" note(s) in " +
+				payload.stats.scannedFolders +
+				" folder(s)" +
+				(payload.scopeAll ? " · scope: all (every notebook)" : "");
+			wrapper.appendChild(meta);
+		}
+
+		el.appendChild(wrapper);
+	}
+
+	function renderNotebookMatrixGroup(
+		group,
+		labels,
+		pageSize,
+		detail,
+		contentScriptId
+	) {
+		const section = document.createElement("section");
+		section.className = "gtd-notebook-view";
+		const heading = document.createElement("h4");
+		heading.className = "gtd-notebook-view-heading";
+		heading.textContent = group.notebookPath;
+		section.appendChild(heading);
+		renderViewWarnings(section, group.warnings);
+		section.appendChild(
+			renderMatrixBoard(
+				group.board,
+				labels,
+				pageSize,
+				detail,
+				contentScriptId
+			)
+		);
+		return section;
+	}
+
+	function renderMatrixBoard(
+		board,
+		labels,
+		pageSize,
+		detail,
+		contentScriptId
+	) {
 		// Axis header row: blank corner + column labels
 		const grid = document.createElement("div");
 		grid.className = "gtd-matrix-grid";
@@ -781,23 +893,16 @@
 			)
 		);
 
-		wrapper.appendChild(grid);
+		return grid;
+	}
 
-		if (payload.stats) {
-			const meta = document.createElement("p");
-			meta.className = "gtd-calendar-debug-meta";
-			meta.textContent =
-				payload.stats.cardCount +
-				" card(s) from " +
-				payload.stats.scannedNotes +
-				" note(s) in " +
-				payload.stats.scannedFolders +
-				" folder(s)" +
-				(payload.scopeAll ? " · scope: all (every notebook)" : "");
-			wrapper.appendChild(meta);
-		}
-
-		el.appendChild(wrapper);
+	function renderViewWarnings(parent, warnings) {
+		(warnings || []).forEach(function (warning) {
+			const warn = document.createElement("p");
+			warn.className = "gtd-calendar-warning";
+			warn.textContent = "⚠ " + warning;
+			parent.appendChild(warn);
+		});
 	}
 
 	function matrixAxisCell(label) {
diff --git a/src/index.ts b/src/index.ts
index 770499e..4acbaf5 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -14,6 +14,10 @@ import parseGanttConfig from "./Gtd/parseGanttConfig";
 import collectGantt from "./Gtd/collectGantt";
 import matrixLabels from "./Gtd/matrixLabels";
 import resolveNotebook from "./Gtd/resolveNotebook";
+import {
+	emptyKanbanLayout,
+	emptyMatrixLayout,
+} from "./Gtd/layoutPayload";
 import { DataAdapter, RawFolder, RawNote } from "./Gtd/types";
 
 const CONTENT_SCRIPT_ID = "gtd-calendar-renderer";
@@ -156,8 +160,7 @@ async function handleGetEvents(message: { rawConfig?: string }) {
 	const config = parseCalendarConfig(rawParsed);
 
 	// 2. Resolve the calendar note (the note being rendered).
-	let sourceNote: { id: string; title: string; parentId: string } | null =
-		null;
+	let sourceNote: { id: string; title: string; parentId: string } | null = null;
 	try {
 		const note = await joplin.workspace.selectedNote();
 		if (note) {
@@ -176,8 +179,7 @@ async function handleGetEvents(message: { rawConfig?: string }) {
 			title: config.title,
 			view: config.view,
 			configError:
-				configError ||
-				"Could not determine which note contains this calendar.",
+				configError || "Could not determine which note contains this calendar.",
 			warnings: config.warnings,
 			sourceNote: null,
 			events: [],
@@ -230,8 +232,7 @@ async function handleGetKanban(message: { rawConfig?: string }) {
 	}
 	const config = parseKanbanConfig(rawParsed);
 
-	let sourceNote: { id: string; title: string; parentId: string } | null =
-		null;
+	let sourceNote: { id: string; title: string; parentId: string } | null = null;
 	try {
 		const note = await joplin.workspace.selectedNote();
 		if (note) {
@@ -246,15 +247,16 @@ async function handleGetKanban(message: { rawConfig?: string }) {
 	}
 
 	if (!sourceNote) {
+		const layout = emptyKanbanLayout(config.groupByNotebook);
 		return {
 			title: config.title,
 			cardDetail: config.cardDetail,
 			pageSize: config.pageSize,
+			scopeAll: config.scopeAll,
 			configError:
-				configError ||
-				"Could not determine which note contains this kanban.",
+				configError || "Could not determine which note contains this kanban.",
 			warnings: config.warnings,
-			board: { backlog: [], inProgress: [], done: [] },
+			layout,
 			stats: null,
 		};
 	}
@@ -280,7 +282,7 @@ async function handleGetKanban(message: { rawConfig?: string }) {
 			...result.warnings,
 			...(softCap ? [softCap] : []),
 		],
-		board: result.board,
+		layout: result.layout,
 		stats: {
 			scannedFolders: result.scannedFolders,
 			scannedNotes: result.scannedNotes,
@@ -299,8 +301,7 @@ async function handleGetMatrix(message: { rawConfig?: string }) {
 	}
 	const config = parseMatrixConfig(rawParsed);
 
-	let sourceNote: { id: string; title: string; parentId: string } | null =
-		null;
+	let sourceNote: { id: string; title: string; parentId: string } | null = null;
 	try {
 		const note = await joplin.workspace.selectedNote();
 		if (note) {
@@ -315,21 +316,17 @@ async function handleGetMatrix(message: { rawConfig?: string }) {
 	}
 
 	if (!sourceNote) {
+		const layout = emptyMatrixLayout(config.groupByNotebook);
 		return {
 			title: config.title,
 			cardDetail: config.cardDetail,
 			pageSize: config.pageSize,
+			scopeAll: config.scopeAll,
 			configError:
-				configError ||
-				"Could not determine which note contains this matrix.",
+				configError || "Could not determine which note contains this matrix.",
 			warnings: config.warnings,
 			labels: matrixLabels(config.mode),
-			board: {
-				topLeft: [],
-				topRight: [],
-				bottomLeft: [],
-				bottomRight: [],
-			},
+			layout,
 			stats: null,
 		};
 	}
@@ -356,7 +353,7 @@ async function handleGetMatrix(message: { rawConfig?: string }) {
 			...(softCap ? [softCap] : []),
 		],
 		labels: matrixLabels(config.mode),
-		board: result.board,
+		layout: result.layout,
 		stats: {
 			scannedFolders: result.scannedFolders,
 			scannedNotes: result.scannedNotes,
@@ -375,8 +372,7 @@ async function handleGetGantt(message: { rawConfig?: string }) {
 	}
 	const config = parseGanttConfig(rawParsed);
 
-	let sourceNote: { id: string; title: string; parentId: string } | null =
-		null;
+	let sourceNote: { id: string; title: string; parentId: string } | null = null;
 	try {
 		const note = await joplin.workspace.selectedNote();
 		if (note) {
@@ -396,8 +392,7 @@ async function handleGetGantt(message: { rawConfig?: string }) {
 			cardDetail: config.cardDetail,
 			scopeAll: config.scopeAll,
 			configError:
-				configError ||
-				"Could not determine which note contains this gantt.",
+				configError || "Could not determine which note contains this gantt.",
 			warnings: config.warnings,
 			chart: { projects: [], rangeStart: null, rangeEnd: null },
 			stats: null,
diff --git a/src/tests/Gtd/folderTree.test.ts b/src/tests/Gtd/folderTree.test.ts
new file mode 100644
index 0000000..1a8d2c6
--- /dev/null
+++ b/src/tests/Gtd/folderTree.test.ts
@@ -0,0 +1,124 @@
+import resolveScopedFolderMetadata, {
+	UNTITLED_NOTEBOOK,
+} from "../../Gtd/folderTree";
+import resolveScopedFolderIds from "../../Gtd/folderScope";
+import { RawFolder } from "../../Gtd/types";
+
+const folders: RawFolder[] = [
+	{ id: "archive-b", parent_id: "beta", title: "Archive" },
+	{ id: "alpha-2", parent_id: "work", title: "alpha" },
+	{ id: "work", parent_id: "", title: "Work" },
+	{ id: "untitled", parent_id: "work", title: "   " },
+	{ id: "archive-a", parent_id: "alpha-1", title: "Archive" },
+	{ id: "beta", parent_id: "work", title: "Beta" },
+	{ id: "alpha-1", parent_id: "work", title: "Alpha" },
+];
+
+describe("resolveScopedFolderMetadata", () => {
+	test("returns root-first deterministic depth-first metadata", () => {
+		const result = resolveScopedFolderMetadata(folders, "work");
+
+		expect(result.map((folder) => folder.id)).toEqual([
+			"work",
+			"alpha-1",
+			"archive-a",
+			"alpha-2",
+			"beta",
+			"archive-b",
+			"untitled",
+		]);
+		expect(result[0]).toEqual({
+			id: "work",
+			parentId: "",
+			title: "Work",
+			notebookPath: "Work",
+		});
+		expect(result.find((folder) => folder.id === "untitled")).toMatchObject({
+			title: UNTITLED_NOTEBOOK,
+			notebookPath: `Work/${UNTITLED_NOTEBOOK}`,
+		});
+	});
+
+	test("is independent of input folder order", () => {
+		const forward = resolveScopedFolderMetadata(folders, "work");
+		const reversed = resolveScopedFolderMetadata([...folders].reverse(), "work");
+		expect(reversed).toEqual(forward);
+	});
+
+	test("uses folder id to break case-insensitive sibling title ties", () => {
+		const result = resolveScopedFolderMetadata(folders, "work");
+		expect(
+			result
+				.filter((folder) => folder.id.startsWith("alpha-"))
+				.map((folder) => folder.id)
+		).toEqual(["alpha-1", "alpha-2"]);
+	});
+
+	test("full paths disambiguate duplicate descendant titles", () => {
+		const result = resolveScopedFolderMetadata(folders, "work");
+		expect(
+			result
+				.filter((folder) => folder.title === "Archive")
+				.map((folder) => folder.notebookPath)
+		).toEqual(["Work/Alpha/Archive", "Work/Beta/Archive"]);
+	});
+
+	test("a selected child root retains its ancestors in the path", () => {
+		const result = resolveScopedFolderMetadata(folders, "alpha-1");
+		expect(result.map((folder) => folder.id)).toEqual([
+			"alpha-1",
+			"archive-a",
+		]);
+		expect(result.map((folder) => folder.notebookPath)).toEqual([
+			"Work/Alpha",
+			"Work/Alpha/Archive",
+		]);
+	});
+
+	test("an orphan root and its descendants remain usable", () => {
+		const malformed: RawFolder[] = [
+			{ id: "orphan", parent_id: "missing", title: "Orphan" },
+			{ id: "child", parent_id: "orphan", title: "Child" },
+		];
+		expect(resolveScopedFolderMetadata(malformed, "orphan")).toEqual([
+			{
+				id: "orphan",
+				parentId: "missing",
+				title: "Orphan",
+				notebookPath: "Orphan",
+			},
+			{
+				id: "child",
+				parentId: "orphan",
+				title: "Child",
+				notebookPath: "Orphan/Child",
+			},
+		]);
+	});
+
+	test("cycles terminate and include each reachable folder once", () => {
+		const cyclic: RawFolder[] = [
+			{ id: "a", parent_id: "b", title: "A" },
+			{ id: "b", parent_id: "a", title: "B" },
+		];
+		const result = resolveScopedFolderMetadata(cyclic, "a");
+		expect(result.map((folder) => folder.id)).toEqual(["a", "b"]);
+		expect(new Set(result.map((folder) => folder.id)).size).toBe(2);
+	});
+
+	test("a missing root returns no metadata", () => {
+		expect(resolveScopedFolderMetadata(folders, "missing")).toEqual([]);
+	});
+
+	test("the existing id-only scope helper remains unchanged", () => {
+		expect(resolveScopedFolderIds(folders, "work", Infinity)).toEqual([
+			"work",
+			"alpha-2",
+			"untitled",
+			"beta",
+			"alpha-1",
+			"archive-b",
+			"archive-a",
+		]);
+	});
+});
\ No newline at end of file
diff --git a/src/tests/Gtd/kanban.test.ts b/src/tests/Gtd/kanban.test.ts
index 3b21e60..a72bd95 100644
--- a/src/tests/Gtd/kanban.test.ts
+++ b/src/tests/Gtd/kanban.test.ts
@@ -62,9 +62,7 @@ describe("parseKanbanConfig", () => {
 		(input) => {
 			const c = parseKanbanConfig({ "page-size": input });
 			expect(c.pageSize).toBe(10);
-			expect(c.warnings).toEqual([
-				`Invalid page-size "${input}" (using 10)`,
-			]);
+			expect(c.warnings).toEqual([`Invalid page-size "${input}" (using 10)`]);
 		}
 	);
 
@@ -137,7 +135,11 @@ function daysAgo(n: number): number {
 describe("collectKanban — bucketing", () => {
 	test("Done wins over in-progress tag", async () => {
 		const notes = [
-			makeNote({ id: "c", title: "Completed but tagged", todo_completed: daysAgo(1) }),
+			makeNote({
+				id: "c",
+				title: "Completed but tagged",
+				todo_completed: daysAgo(1),
+			}),
 		];
 		const result = await collectKanban(
 			makeAdapter(folders, notes, { c: ["in-progress"] }),
@@ -185,10 +187,7 @@ describe("collectKanban — bucketing", () => {
 			NOW
 		);
 
-		expect(result.board.backlog.map((c) => c.id)).toEqual([
-			"t",
-			"gtd-note",
-		]);
+		expect(result.board.backlog.map((c) => c.id)).toEqual(["t", "gtd-note"]);
 		expect(result.board.backlog[1]).toMatchObject({
 			isTodo: false,
 			completed: false,
@@ -245,9 +244,7 @@ describe("collectKanban — bucketing", () => {
 
 		expect(result.board.backlog.map((c) => c.id)).toEqual(["broken-note"]);
 		expect(result.warnings).toHaveLength(1);
-		expect(result.warnings[0]).toContain(
-			'"Broken note": gtd block problem'
-		);
+		expect(result.warnings[0]).toContain('"Broken note": gtd block problem');
 	});
 
 	test.each([
@@ -436,15 +433,13 @@ describe("collectKanban — mixed note/to-do contracts", () => {
 		);
 
 		expect(result.cardCount).toBe(3);
-		expect([
-			...result.board.backlog,
-			...result.board.inProgress,
-			...result.board.done,
-		].map((card) => card.id)).toEqual([
-			"backlog-todo",
-			"active-note",
-			"done-todo",
-		]);
+		expect(
+			[
+				...result.board.backlog,
+				...result.board.inProgress,
+				...result.board.done,
+			].map((card) => card.id)
+		).toEqual(["backlog-todo", "active-note", "done-todo"]);
 	});
 });
 describe("collectKanban — done window", () => {
@@ -556,3 +551,119 @@ describe("collectKanban — recurrence flag", () => {
 		expect(result.board.backlog[0].isRecurring).toBe(true);
 	});
 });
+
+describe("collectKanban — notebook groups", () => {
+	test("builds sorted exact-owner groups and omits empty folders", async () => {
+		const tree: RawFolder[] = [
+			{ id: "root-board", parent_id: "", title: "Projects" },
+			{ id: "empty", parent_id: "root-board", title: "Empty" },
+			{ id: "work", parent_id: "root-board", title: "Work" },
+			{ id: "release", parent_id: "work", title: "Release" },
+		];
+		const notes = [
+			makeNote({ id: "host", parent_id: "root-board", is_todo: 0 }),
+			makeNote({ id: "root-card", parent_id: "root-board", title: "Root" }),
+			makeNote({ id: "work-z", parent_id: "work", is_todo: 0, title: "Zulu" }),
+			makeNote({ id: "work-b", parent_id: "work", title: "Bravo" }),
+			makeNote({ id: "work-a", parent_id: "work", title: "Alpha" }),
+			makeNote({
+				id: "old-done",
+				parent_id: "empty",
+				todo_completed: daysAgo(30),
+			}),
+			makeNote({
+				id: "broken",
+				parent_id: "release",
+				is_todo: 0,
+				title: "Broken",
+				body: "```gtd\ntitle: [invalid\n```",
+			}),
+		];
+		const result = await collectKanban(
+			makeAdapter(tree, notes, { "work-z": ["in-progress"] }),
+			"host",
+			"root-board",
+			parseKanbanConfig({
+				scope: "children",
+				group: "notebook",
+				todos: "all",
+				"sort-type": "title",
+				"done-window": 7,
+			}),
+			NOW
+		);
+
+		expect(result.layout.kind).toBe("notebooks");
+		if (result.layout.kind !== "notebooks")
+			throw new Error("grouped layout expected");
+		expect(result.layout.groups.map((group) => group.folderId)).toEqual([
+			"root-board",
+			"work",
+			"release",
+		]);
+		expect(result.layout.groups.map((group) => group.notebookPath)).toEqual([
+			"Projects",
+			"Projects/Work",
+			"Projects/Work/Release",
+		]);
+		expect(
+			result.layout.groups[1].board.backlog.map((card) => card.id)
+		).toEqual(["work-a", "work-b"]);
+		expect(
+			result.layout.groups[1].board.inProgress.map((card) => card.id)
+		).toEqual(["work-z"]);
+		expect(result.layout.groups[2].warnings).toHaveLength(1);
+		expect(result.board.backlog).toHaveLength(0);
+		expect(result.scannedFolders).toBe(4);
+		expect(result.scannedNotes).toBe(7);
+		expect(result.cardCount).toBe(5);
+		expect(
+			result.layout.groups.reduce((sum, group) => sum + group.cardCount, 0)
+		).toBe(5);
+	});
+
+	test("retains the single layout when notebook grouping is off", async () => {
+		const result = await collectKanban(
+			makeAdapter(folders, [makeNote({ id: "one" })]),
+			"host",
+			"board",
+			parseKanbanConfig({ scope: "children", todos: "all" }),
+			NOW
+		);
+		expect(result.layout).toMatchObject({
+			kind: "single",
+			board: result.board,
+		});
+	});
+
+	test.each([
+		["this-folder", "this-folder", 1],
+		["numeric depth", 1, 2],
+		["scope all", "all", 4],
+	] as const)(
+		"retains one aggregate view for %s",
+		async (_label, scope, count) => {
+			const tree: RawFolder[] = [
+				{ id: "board", parent_id: "", title: "Board" },
+				{ id: "child", parent_id: "board", title: "Child" },
+				{ id: "grand", parent_id: "child", title: "Grand" },
+				{ id: "other", parent_id: "", title: "Other" },
+			];
+			const notes = tree.map((folder) =>
+				makeNote({ id: "card-" + folder.id, parent_id: folder.id })
+			);
+			const result = await collectKanban(
+				makeAdapter(tree, notes),
+				"host",
+				"board",
+				parseKanbanConfig({ scope, todos: "all" }),
+				NOW
+			);
+			expect(result.layout.kind).toBe("single");
+			expect(result.cardCount).toBe(count);
+			if (result.layout.kind !== "single")
+				throw new Error("single layout expected");
+			expect(result.layout.board.backlog).toHaveLength(count);
+		}
+	);
+});
diff --git a/src/tests/Gtd/layoutPayload.test.ts b/src/tests/Gtd/layoutPayload.test.ts
new file mode 100644
index 0000000..87a50d3
--- /dev/null
+++ b/src/tests/Gtd/layoutPayload.test.ts
@@ -0,0 +1,19 @@
+import {
+	emptyKanbanLayout,
+	emptyMatrixLayout,
+} from "../../Gtd/layoutPayload";
+
+describe("layout payload helpers", () => {
+	test("missing-source layouts retain the requested discriminator", () => {
+		expect(emptyKanbanLayout(false)).toEqual({
+			kind: "single",
+			board: { backlog: [], inProgress: [], done: [] },
+		});
+		expect(emptyKanbanLayout(true)).toEqual({ kind: "notebooks", groups: [] });
+		expect(emptyMatrixLayout(false)).toEqual({
+			kind: "single",
+			board: { topLeft: [], topRight: [], bottomLeft: [], bottomRight: [] },
+		});
+		expect(emptyMatrixLayout(true)).toEqual({ kind: "notebooks", groups: [] });
+	});
+});
diff --git a/src/tests/Gtd/matrix.test.ts b/src/tests/Gtd/matrix.test.ts
index 46b0bc2..242c2d4 100644
--- a/src/tests/Gtd/matrix.test.ts
+++ b/src/tests/Gtd/matrix.test.ts
@@ -42,16 +42,12 @@ describe("parseMatrixConfig", () => {
 		(input) => {
 			const c = parseMatrixConfig({ "page-size": input });
 			expect(c.pageSize).toBe(10);
-			expect(c.warnings).toEqual([
-				`Invalid page-size "${input}" (using 10)`,
-			]);
+			expect(c.warnings).toEqual([`Invalid page-size "${input}" (using 10)`]);
 		}
 	);
 
 	test("mode parses and warns on invalid", () => {
-		expect(parseMatrixConfig({ mode: "eisenhower" }).mode).toBe(
-			"eisenhower"
-		);
+		expect(parseMatrixConfig({ mode: "eisenhower" }).mode).toBe("eisenhower");
 		const bad = parseMatrixConfig({ mode: "wiebe" });
 		expect(bad.mode).toBe("skeleton");
 		expect(bad.warnings.some((w) => w.includes("mode"))).toBe(true);
@@ -71,9 +67,7 @@ describe("parseMatrixConfig", () => {
 			"urgent-tag": "now",
 			"important-tag": "NOW",
 		});
-		expect(c.warnings.some((w) => w.includes("will not separate"))).toBe(
-			true
-		);
+		expect(c.warnings.some((w) => w.includes("will not separate"))).toBe(true);
 	});
 
 	test("invalid values warn and fall back", () => {
@@ -347,9 +341,7 @@ describe("collectMatrix — mixed note/to-do contracts", () => {
 		]);
 		expect(result.cardCount).toBe(2);
 		expect(result.warnings).toHaveLength(1);
-		expect(result.warnings[0]).toContain(
-			'"Broken note": gtd block problem'
-		);
+		expect(result.warnings[0]).toContain('"Broken note": gtd block problem');
 	});
 
 	test.each([
@@ -504,9 +496,7 @@ describe("collectMatrix — Skeleton mode", () => {
 			NOW
 		);
 		expect(result.board.bottomLeft.map((c) => c.id)).toEqual(["edge"]);
-		expect(result.board.bottomRight.map((c) => c.id)).toEqual([
-			"past-edge",
-		]);
+		expect(result.board.bottomRight.map((c) => c.id)).toEqual(["past-edge"]);
 	});
 
 	test("gtd date override affects due-soon just like a due date", async () => {
@@ -522,3 +512,164 @@ describe("collectMatrix — Skeleton mode", () => {
 		expect(result.board.bottomLeft.map((c) => c.id)).toEqual(["g"]);
 	});
 });
+
+describe("collectMatrix — notebook groups", () => {
+	test.each(["skeleton", "eisenhower"] as const)(
+		"groups mixed cards exactly once in %s mode",
+		async (mode) => {
+			const tree: RawFolder[] = [
+				{ id: "root-board", parent_id: "", title: "Projects" },
+				{ id: "empty", parent_id: "root-board", title: "Empty" },
+				{ id: "child", parent_id: "root-board", title: "Child" },
+			];
+			const notes = [
+				makeNote({ id: "host", parent_id: "root-board", is_todo: 0 }),
+				makeNote({ id: "root-note", parent_id: "root-board", is_todo: 0 }),
+				makeNote({ id: "child-todo", parent_id: "child" }),
+				makeNote({
+					id: "child-plain",
+					parent_id: "child",
+					is_todo: 0,
+					title: "Alpha",
+				}),
+				makeNote({
+					id: "broken",
+					parent_id: "child",
+					is_todo: 0,
+					title: "Broken",
+					body: "```gtd\ntitle: [invalid\n```",
+				}),
+				makeNote({ id: "done", parent_id: "empty", todo_completed: 1 }),
+			];
+			const result = await collectMatrix(
+				makeAdapter(tree, notes, {
+					"root-note": ["important", "in-progress"],
+					"child-todo": ["urgent"],
+				}),
+				"host",
+				"root-board",
+				parseMatrixConfig({
+					scope: "children",
+					group: "notebook",
+					todos: "all",
+					mode,
+					"sort-type": "title",
+				})
+			);
+
+			expect(result.layout.kind).toBe("notebooks");
+			if (result.layout.kind !== "notebooks")
+				throw new Error("grouped layout expected");
+			expect(result.layout.groups.map((group) => group.folderId)).toEqual([
+				"root-board",
+				"child",
+			]);
+			expect(result.layout.groups[0].cardCount).toBe(1);
+			expect(result.layout.groups[1].cardCount).toBe(3);
+			expect(result.layout.groups[1].warnings).toHaveLength(1);
+			expect(
+				result.layout.groups[1].board.bottomRight.map((card) => card.id)
+			).toEqual(["child-plain", "broken"]);
+			const ids = result.layout.groups.flatMap((group) =>
+				[
+					...group.board.topLeft,
+					...group.board.topRight,
+					...group.board.bottomLeft,
+					...group.board.bottomRight,
+				].map((card) => card.id)
+			);
+			expect(ids.sort()).toEqual([
+				"broken",
+				"child-plain",
+				"child-todo",
+				"root-note",
+			]);
+			expect(result.board.bottomRight).toHaveLength(0);
+			expect(result.scannedFolders).toBe(3);
+			expect(result.scannedNotes).toBe(6);
+			expect(result.cardCount).toBe(4);
+		}
+	);
+
+	test("retains the single layout when notebook grouping is off", async () => {
+		const result = await collectMatrix(
+			makeAdapter(folders, [makeNote({ id: "one" })]),
+			"host",
+			"board",
+			parseMatrixConfig({ scope: "children", todos: "all" })
+		);
+		expect(result.layout).toMatchObject({
+			kind: "single",
+			board: result.board,
+		});
+	});
+
+	test.each(["skeleton", "eisenhower"] as const)(
+		"keeps all four %s quadrants local to the owning notebook",
+		async (mode) => {
+			const tree: RawFolder[] = [
+				{ id: "root-board", parent_id: "", title: "Projects" },
+				{ id: "child", parent_id: "root-board", title: "Child" },
+			];
+			const notes = [
+				makeNote({ id: "root-left", parent_id: "root-board", is_todo: 0 }),
+				makeNote({ id: "tl", parent_id: "child", is_todo: 0 }),
+				makeNote({ id: "tr", parent_id: "child", is_todo: 0 }),
+				makeNote({ id: "bl", parent_id: "child", is_todo: 0 }),
+				makeNote({ id: "br", parent_id: "child", is_todo: 0 }),
+			];
+			const tags = {
+				"root-left": ["urgent"],
+				tl: ["urgent", "important", "in-progress"],
+				tr: ["important", "in-progress"],
+				bl: ["urgent"],
+			};
+			const result = await collectMatrix(
+				makeAdapter(tree, notes, tags),
+				"host",
+				"root-board",
+				parseMatrixConfig({ scope: "children", group: "notebook", mode })
+			);
+			expect(result.layout.kind).toBe("notebooks");
+			if (result.layout.kind !== "notebooks")
+				throw new Error("grouped layout expected");
+			const root = result.layout.groups[0].board;
+			const child = result.layout.groups[1].board;
+			expect(root.bottomLeft.map((card) => card.id)).toEqual(["root-left"]);
+			expect(child.topLeft.map((card) => card.id)).toEqual(["tl"]);
+			expect(child.topRight.map((card) => card.id)).toEqual(["tr"]);
+			expect(child.bottomLeft.map((card) => card.id)).toEqual(["bl"]);
+			expect(child.bottomRight.map((card) => card.id)).toEqual(["br"]);
+		}
+	);
+
+	test.each([
+		["this-folder", "this-folder", 1],
+		["numeric depth", 1, 2],
+		["scope all", "all", 4],
+	] as const)(
+		"retains one aggregate matrix for %s",
+		async (_label, scope, count) => {
+			const tree: RawFolder[] = [
+				{ id: "board", parent_id: "", title: "Board" },
+				{ id: "child", parent_id: "board", title: "Child" },
+				{ id: "grand", parent_id: "child", title: "Grand" },
+				{ id: "other", parent_id: "", title: "Other" },
+			];
+			const notes = tree.map((folder) =>
+				makeNote({ id: "card-" + folder.id, parent_id: folder.id })
+			);
+			const result = await collectMatrix(
+				makeAdapter(tree, notes),
+				"host",
+				"board",
+				parseMatrixConfig({ scope, todos: "all", mode: "eisenhower" })
+			);
+			expect(result.layout.kind).toBe("single");
+			expect(result.cardCount).toBe(count);
+			if (result.layout.kind !== "single")
+				throw new Error("single layout expected");
+			expect(result.layout.board.bottomRight).toHaveLength(count);
+		}
+	);
+});
diff --git a/src/tests/Gtd/scopeGrouping.test.ts b/src/tests/Gtd/scopeGrouping.test.ts
new file mode 100644
index 0000000..51d63c5
--- /dev/null
+++ b/src/tests/Gtd/scopeGrouping.test.ts
@@ -0,0 +1,83 @@
+import parseKanbanConfig from "../../Gtd/parseKanbanConfig";
+import parseMatrixConfig from "../../Gtd/parseMatrixConfig";
+
+const parsers = [
+	["kanban", parseKanbanConfig],
+	["matrix", parseMatrixConfig],
+] as const;
+
+describe.each(parsers)("%s notebook grouping config", (_name, parse) => {
+	test("requires both literal scope: children and group: notebook", () => {
+		const grouped = parse({ scope: "children", group: "notebook" });
+		expect(grouped.scopeDepth).toBe(Infinity);
+		expect(grouped.scopeAll).toBe(false);
+		expect(grouped.groupByNotebook).toBe(true);
+		expect(grouped.warnings).toHaveLength(0);
+	});
+
+	test("scope: children remains aggregated when group is omitted", () => {
+		const config = parse({ scope: "children" });
+		expect(config.scopeDepth).toBe(Infinity);
+		expect(config.groupByNotebook).toBe(false);
+		expect(config.warnings).toHaveLength(0);
+	});
+
+	test.each([
+		["omitted", {}, 0],
+		["this-folder", { scope: "this-folder" }, 0],
+		["numeric", { scope: 3 }, 3],
+		["numeric string", { scope: "3" }, 3],
+	])("%s scope remains non-grouped", (_label, raw, expectedDepth) => {
+		const config = parse(raw);
+		expect(config.scopeDepth).toBe(expectedDepth);
+		expect(config.scopeAll).toBe(false);
+		expect(config.groupByNotebook).toBe(false);
+		expect(config.warnings).toHaveLength(0);
+	});
+
+	test("scope: all remains non-grouped", () => {
+		const config = parse({ scope: "all" });
+		expect(config.scopeAll).toBe(true);
+		expect(config.scopeDepth).toBe(0);
+		expect(config.groupByNotebook).toBe(false);
+		expect(config.warnings).toHaveLength(0);
+	});
+
+	test("scope: all stays non-grouped and retains notebook conflict warnings", () => {
+		const config = parse({ scope: "all", notebook: "Work" });
+		expect(config.scopeAll).toBe(true);
+		expect(config.groupByNotebook).toBe(false);
+		expect(config.warnings).toEqual([
+			'"notebook" is ignored when scope: all (scanning every notebook)',
+		]);
+	});
+
+	test("group: notebook with another scope warns and remains non-grouped", () => {
+		const config = parse({ scope: "all", group: "notebook" });
+		expect(config.scopeAll).toBe(true);
+		expect(config.groupByNotebook).toBe(false);
+		expect(config.warnings).toEqual([
+			'"group: notebook" requires scope: children (grouping disabled)',
+		]);
+	});
+
+	test("an unsupported group value warns and remains non-grouped", () => {
+		const config = parse({ scope: "children", group: "folder" });
+		expect(config.scopeDepth).toBe(Infinity);
+		expect(config.groupByNotebook).toBe(false);
+		expect(config.warnings).toEqual([
+			'Invalid group "folder" (grouping disabled)',
+		]);
+	});
+
+	test("invalid scope fallback remains non-grouped", () => {
+		const config = parse({ scope: "descendants", group: "notebook" });
+		expect(config.scopeDepth).toBe(0);
+		expect(config.scopeAll).toBe(false);
+		expect(config.groupByNotebook).toBe(false);
+		expect(config.warnings).toEqual([
+			'Invalid scope "descendants" (using "this-folder")',
+			'"group: notebook" requires scope: children (grouping disabled)',
+		]);
+	});
+});