diff --git a/src/renderer/App.tsx b/src/renderer/App.tsx
index 00f714e..88e85e3 100644
--- a/src/renderer/App.tsx
+++ b/src/renderer/App.tsx
@@ -1,6 +1,7 @@
 import { useEffect, useState } from 'react'
 import { FileTree } from './components/FileTree/FileTree'
 import { MarkdownEditor } from './components/Editor/MarkdownEditor'
+import { DocumentOutline } from './components/Editor/DocumentOutline'
 import { ChatPanel } from './components/AIChat/ChatPanel'
 import { AnalysisToolbar } from './components/Toolbar/AnalysisToolbar'
 import { RevisionPanel } from './components/Revisions/RevisionPanel'
@@ -10,7 +11,7 @@ import './styles/app.css'
 export default function App(): JSX.Element {
   const {
     setFileTree, activeFilePath, isDirty, markSaved, activeFileContent, theme, toggleTheme,
-    loadSession, revisionPanelOpen, toggleRevisionPanel
+    loadSession, revisionPanelOpen, toggleRevisionPanel, outlineOpen
   } = useEditorStore()
   const [sidebarOpen, setSidebarOpen] = useState(
     () => localStorage.getItem('sidebarOpen') !== 'false'
@@ -87,7 +88,10 @@ export default function App(): JSX.Element {
       </aside>
       <main className="editor-area" style={{ position: 'relative' }}>
         <AnalysisToolbar />
-        <MarkdownEditor />
+        <div className="editor-body">
+          {outlineOpen && <DocumentOutline />}
+          <MarkdownEditor />
+        </div>
         {revisionPanelOpen && <RevisionPanel />}
       </main>
       <aside className="chat-area">
diff --git a/src/renderer/components/Editor/DocumentOutline.css b/src/renderer/components/Editor/DocumentOutline.css
new file mode 100644
index 0000000..b19e51c
--- /dev/null
+++ b/src/renderer/components/Editor/DocumentOutline.css
@@ -0,0 +1,89 @@
+.outline-panel {
+  width: 160px;
+  min-width: 160px;
+  flex-shrink: 0;
+  background: var(--sidebar-bg);
+  border-right: 1px solid var(--border);
+  display: flex;
+  flex-direction: column;
+  overflow: hidden;
+}
+
+.outline-header {
+  padding: 14px 12px 10px;
+  font-size: 11px;
+  font-weight: 700;
+  letter-spacing: 0.12em;
+  color: var(--text-muted);
+  border-bottom: 1px solid var(--border);
+  text-transform: uppercase;
+  flex-shrink: 0;
+}
+
+.outline-list {
+  flex: 1;
+  overflow-y: auto;
+  padding: 4px 0;
+}
+
+.outline-empty {
+  padding: 12px 12px;
+  font-size: 11px;
+  font-family: var(--font-sans);
+  color: var(--text-muted);
+  opacity: 0.5;
+}
+
+/* Base item style — reset button defaults */
+.outline-item {
+  display: block;
+  width: 100%;
+  background: none;
+  border: none;
+  cursor: pointer;
+  text-align: left;
+  font-family: var(--font-sans);
+  font-size: 11px;
+  color: var(--text-secondary);
+  padding: 4px 8px;
+  line-height: 1.4;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  transition: background 0.1s, color 0.1s;
+}
+
+.outline-item:hover {
+  background: rgba(167, 139, 95, 0.12);
+  color: var(--text-primary);
+}
+
+/* Heading indent levels */
+.outline-item--h1 {
+  padding-left: 8px;
+  font-weight: 600;
+  color: var(--text-primary);
+}
+
+.outline-item--h2 {
+  padding-left: 18px;
+}
+
+.outline-item--h3 {
+  padding-left: 28px;
+  color: var(--text-muted);
+  font-size: 10.5px;
+}
+
+/* Divider row */
+.outline-divider {
+  padding-left: 8px;
+  color: var(--text-muted);
+  opacity: 0.5;
+  letter-spacing: 0.05em;
+  font-size: 10px;
+}
+
+.outline-divider:hover {
+  opacity: 1;
+}
diff --git a/src/renderer/components/Editor/DocumentOutline.tsx b/src/renderer/components/Editor/DocumentOutline.tsx
new file mode 100644
index 0000000..5fac506
--- /dev/null
+++ b/src/renderer/components/Editor/DocumentOutline.tsx
@@ -0,0 +1,82 @@
+import { useMemo } from 'react'
+import { EditorView } from '@codemirror/view'
+import { useEditorStore } from '../../store/editorStore'
+import { currentEditorView } from './MarkdownEditor'
+import './DocumentOutline.css'
+
+type OutlineItem =
+  | { type: 'heading'; level: 1 | 2 | 3; text: string; offset: number; key: string }
+  | { type: 'divider'; offset: number; nth: number; key: string }
+
+function parseOutline(content: string): OutlineItem[] {
+  const items: OutlineItem[] = []
+  const lines = content.split('\n')
+  let offset = 0
+  let dividerCount = 0
+
+  for (const line of lines) {
+    const headingMatch = line.match(/^(#{1,3})\s+(.+)/)
+    if (headingMatch) {
+      const level = headingMatch[1].length as 1 | 2 | 3
+      const text = headingMatch[2].trim()
+      items.push({ type: 'heading', level, text, offset, key: `h-${offset}` })
+    } else if (/^(-{3,}|\*{3,}|_{3,})\s*$/.test(line)) {
+      dividerCount++
+      items.push({ type: 'divider', offset, nth: dividerCount, key: `d-${offset}` })
+    }
+    offset += line.length + 1
+  }
+
+  return items
+}
+
+function navigateTo(offset: number): void {
+  const view = currentEditorView
+  if (!view) return
+  view.dispatch({
+    selection: { anchor: offset },
+    effects: EditorView.scrollIntoView(offset, { y: 'start' })
+  })
+  view.focus()
+}
+
+export function DocumentOutline(): JSX.Element {
+  const activeFileContent = useEditorStore((s) => s.activeFileContent)
+  const items = useMemo(() => parseOutline(activeFileContent), [activeFileContent])
+
+  return (
+    <div className="outline-panel">
+      <div className="outline-header">OUTLINE</div>
+      <div className="outline-list">
+        {items.length === 0 ? (
+          <div className="outline-empty">No headings</div>
+        ) : (
+          items.map((item) => {
+            if (item.type === 'heading') {
+              return (
+                <button
+                  key={item.key}
+                  className={`outline-item outline-item--h${item.level}`}
+                  onClick={() => navigateTo(item.offset)}
+                  title={item.text}
+                >
+                  {item.text}
+                </button>
+              )
+            }
+            return (
+              <button
+                key={item.key}
+                className="outline-item outline-divider"
+                onClick={() => navigateTo(item.offset)}
+                title={`Divider ${item.nth}`}
+              >
+                ———
+              </button>
+            )
+          })
+        )}
+      </div>
+    </div>
+  )
+}
diff --git a/src/renderer/components/Toolbar/AnalysisToolbar.tsx b/src/renderer/components/Toolbar/AnalysisToolbar.tsx
index 29f2569..5863dac 100644
--- a/src/renderer/components/Toolbar/AnalysisToolbar.tsx
+++ b/src/renderer/components/Toolbar/AnalysisToolbar.tsx
@@ -63,7 +63,9 @@ export function AnalysisToolbar(): JSX.Element {
     setProjectWordCount,
     fontSize,
     setFontSize,
-    setRightPanelTab
+    setRightPanelTab,
+    outlineOpen,
+    toggleOutline
   } = useEditorStore()
 
   useEffect(() => {
@@ -297,6 +299,13 @@ export function AnalysisToolbar(): JSX.Element {
       </div>
 
       <div className="toolbar-right">
+        <button
+          className={`toolbar-btn toolbar-btn-outline${outlineOpen ? ' active' : ''}`}
+          onClick={toggleOutline}
+          title={outlineOpen ? 'Hide document outline' : 'Show document outline'}
+        >
+          ≡
+        </button>
         <div className="toolbar-fontsize">
           <button
             className="toolbar-fontsize-btn"
diff --git a/src/renderer/components/Toolbar/Toolbar.css b/src/renderer/components/Toolbar/Toolbar.css
index f83d0a6..78ba1e0 100644
--- a/src/renderer/components/Toolbar/Toolbar.css
+++ b/src/renderer/components/Toolbar/Toolbar.css
@@ -141,6 +141,14 @@
   opacity: 0.5;
 }
 
+/* ── Outline toggle button ───────────────────────────────────────── */
+.toolbar-btn-outline {
+  padding: 4px 8px;
+  font-size: 14px;
+  line-height: 1;
+  flex-shrink: 0;
+}
+
 /* ── Story Bible toolbar ─────────────────────────────────────────── */
 .toolbar-bible-label {
   font-size: 9px;
diff --git a/src/renderer/store/editorStore.ts b/src/renderer/store/editorStore.ts
index b9bd63b..25ab80f 100644
--- a/src/renderer/store/editorStore.ts
+++ b/src/renderer/store/editorStore.ts
@@ -81,6 +81,10 @@ interface EditorState {
   rightPanelTab: 'chat' | 'feedback'
   setRightPanelTab: (tab: 'chat' | 'feedback') => void
 
+  // Document outline panel
+  outlineOpen: boolean
+  toggleOutline: () => void
+
   // Session persistence
   loadSession: () => Promise<void>
 }
@@ -522,6 +526,14 @@ export const useEditorStore = create<EditorState>((set, get) => ({
 
   rightPanelTab: 'chat',
   setRightPanelTab: (tab) => set({ rightPanelTab: tab }),
+
+  outlineOpen: localStorage.getItem('outlineOpen') === 'true',
+  toggleOutline: () => set((s) => {
+    const next = !s.outlineOpen
+    localStorage.setItem('outlineOpen', String(next))
+    return { outlineOpen: next }
+  }),
+
   revisions: [],
   setRevisions: (revisions) => set({ revisions }),
 
diff --git a/src/renderer/styles/app.css b/src/renderer/styles/app.css
index 562ad73..255e965 100644
--- a/src/renderer/styles/app.css
+++ b/src/renderer/styles/app.css
@@ -140,6 +140,15 @@
   background: var(--editor-bg);
 }
 
+/* Flex row containing the optional outline panel + the CodeMirror editor */
+.editor-body {
+  flex: 1;
+  display: flex;
+  flex-direction: row;
+  overflow: hidden;
+  min-height: 0;
+}
+
 /* ─── Chat area ────────────────────────────────────────────────── */
 .chat-area {
   overflow: hidden;