diff --git a/frontend/src/App.jsx b/frontend/src/App.jsx
index f6f119b..f8f01ab 100644
--- a/frontend/src/App.jsx
+++ b/frontend/src/App.jsx
@@ -9,6 +9,7 @@ import EntriesView from './components/EntriesView'
 import RunsView from './components/RunsView'
 import AdminView from './components/AdminView'
 import TagsView from './components/TagsView'
+import CollectionsView from './components/CollectionsView'
 import ContextRail from './components/ContextRail'
 
 export const AuthContext = createContext(null);
@@ -213,6 +214,9 @@ export default function App() {
                 onViewChange={handleViewChange}
               />
             )}
+            {view === 'collections' && (
+              <CollectionsView archiveId={archiveId} />
+            )}
           </div>
           <ContextRail
             archiveId={archiveId}
diff --git a/frontend/src/api.js b/frontend/src/api.js
index 8c5d9bb..aa5695a 100644
--- a/frontend/src/api.js
+++ b/frontend/src/api.js
@@ -168,6 +168,67 @@ export async function createRole(slug, name) {
   return res.json();
 }
 
+// ── Collection helpers ─────────────────────────────────────────────────────
+
+export async function listCollections(archiveId) {
+  return getJson(`/api/archives/${archiveId}/collections`);
+}
+
+export async function createCollection(archiveId, name, slug, defaultVisibilityBits = 2) {
+  const res = await fetch(`/api/archives/${archiveId}/collections`, {
+    method: 'POST',
+    headers: { 'content-type': 'application/json' },
+    body: JSON.stringify({ name, slug, default_visibility_bits: defaultVisibilityBits }),
+  });
+  if (!res.ok) {
+    const err = await res.json().catch(() => ({ error: res.statusText }));
+    throw new Error(err.error || res.statusText);
+  }
+  return res.json();
+}
+
+export async function getCollection(archiveId, collUid) {
+  return getJson(`/api/archives/${archiveId}/collections/${collUid}`);
+}
+
+export async function addEntryToCollection(archiveId, collUid, entryUid, visibilityBits = 2) {
+  const res = await fetch(`/api/archives/${archiveId}/collections/${collUid}/entries`, {
+    method: 'POST',
+    headers: { 'content-type': 'application/json' },
+    body: JSON.stringify({ entry_uid: entryUid, visibility_bits: visibilityBits }),
+  });
+  if (!res.ok) {
+    const err = await res.json().catch(() => ({ error: res.statusText }));
+    throw new Error(err.error || res.statusText);
+  }
+}
+
+export async function removeEntryFromCollection(archiveId, collUid, entryUid) {
+  const res = await fetch(`/api/archives/${archiveId}/collections/${collUid}/entries/${entryUid}`, {
+    method: 'DELETE',
+  });
+  if (!res.ok) {
+    const err = await res.json().catch(() => ({ error: res.statusText }));
+    throw new Error(err.error || res.statusText);
+  }
+}
+
+export async function updateEntryVisibility(archiveId, collUid, entryUid, visibilityBits) {
+  const res = await fetch(`/api/archives/${archiveId}/collections/${collUid}/entries/${entryUid}`, {
+    method: 'PATCH',
+    headers: { 'content-type': 'application/json' },
+    body: JSON.stringify({ visibility_bits: visibilityBits }),
+  });
+  if (!res.ok) {
+    const err = await res.json().catch(() => ({ error: res.statusText }));
+    throw new Error(err.error || res.statusText);
+  }
+}
+
+export async function listEntryCollections(archiveId, entryUid) {
+  return getJson(`/api/archives/${archiveId}/entries/${entryUid}/collections`);
+}
+
 // ── 401 interceptor ───────────────────────────────────────────────────────────
 const _origFetch = window.fetch;
 window.fetch = async (...args) => {
diff --git a/frontend/src/components/CollectionsView.jsx b/frontend/src/components/CollectionsView.jsx
new file mode 100644
index 0000000..bd542e7
--- /dev/null
+++ b/frontend/src/components/CollectionsView.jsx
@@ -0,0 +1,165 @@
+import { useState, useEffect, useCallback } from 'react'
+import { listCollections, createCollection, getCollection } from '../api.js'
+
+const VIS_LABELS = { 0: 'Private', 1: 'Public', 2: 'Users only', 3: 'Public' }
+
+export default function CollectionsView({ archiveId }) {
+  const [collections, setCollections] = useState([])
+  const [loading, setLoading] = useState(false)
+  const [error, setError] = useState(null)
+  const [selectedColl, setSelectedColl] = useState(null)
+  const [collDetail, setCollDetail] = useState(null)
+  const [detailLoading, setDetailLoading] = useState(false)
+
+  // Create form
+  const [newName, setNewName] = useState('')
+  const [newSlug, setNewSlug] = useState('')
+  const [newVis, setNewVis] = useState(2)
+  const [creating, setCreating] = useState(false)
+  const [createError, setCreateError] = useState(null)
+
+  const refresh = useCallback(async () => {
+    if (!archiveId) return
+    setLoading(true)
+    setError(null)
+    try {
+      const cols = await listCollections(archiveId)
+      setCollections(cols)
+    } catch (e) {
+      setError(e.message)
+    } finally {
+      setLoading(false)
+    }
+  }, [archiveId])
+
+  useEffect(() => { refresh() }, [refresh])
+
+  useEffect(() => {
+    if (!selectedColl) { setCollDetail(null); return }
+    setDetailLoading(true)
+    getCollection(archiveId, selectedColl.collection_uid)
+      .then(d => setCollDetail(d))
+      .catch(e => setError(e.message))
+      .finally(() => setDetailLoading(false))
+  }, [selectedColl, archiveId])
+
+  async function handleCreate(e) {
+    e.preventDefault()
+    const name = newName.trim()
+    const slug = newSlug.trim()
+    if (!name || !slug) return
+    setCreating(true)
+    setCreateError(null)
+    try {
+      await createCollection(archiveId, name, slug, newVis)
+      setNewName('')
+      setNewSlug('')
+      setNewVis(2)
+      await refresh()
+    } catch (err) {
+      setCreateError(err.message)
+    } finally {
+      setCreating(false)
+    }
+  }
+
+  if (!archiveId) return <div className="view-placeholder">Select an archive.</div>
+
+  return (
+    <div className="collections-view">
+      <h2 className="view-heading">Collections</h2>
+
+      {loading && <div className="muted">Loading…</div>}
+      {error && <div className="error-text">{error}</div>}
+
+      <div className="collections-layout">
+        <div className="collections-list">
+          {collections.map(c => (
+            <div
+              key={c.collection_uid}
+              className={`collection-row${selectedColl?.collection_uid === c.collection_uid ? ' is-selected' : ''}`}
+              onClick={() => setSelectedColl(c)}
+            >
+              <span className="collection-name">{c.name}</span>
+              <span className="muted" style={{ fontSize: '0.8em' }}>
+                {VIS_LABELS[c.default_visibility_bits] ?? c.default_visibility_bits}
+              </span>
+            </div>
+          ))}
+          {collections.length === 0 && !loading && (
+            <div className="muted">No collections yet.</div>
+          )}
+        </div>
+
+        {selectedColl && (
+          <div className="collection-detail">
+            <h3 className="collection-detail-name">{selectedColl.name}</h3>
+            <div className="muted" style={{ marginBottom: '0.75rem' }}>
+              Default visibility: {VIS_LABELS[selectedColl.default_visibility_bits] ?? selectedColl.default_visibility_bits}
+            </div>
+            {detailLoading ? (
+              <div className="muted">Loading entries…</div>
+            ) : collDetail ? (
+              collDetail.entries.length === 0 ? (
+                <div className="muted">No entries visible to you in this collection.</div>
+              ) : (
+                <ul className="collection-entries-list">
+                  {collDetail.entries.map(entry => (
+                    <li key={entry.entry_uid} className="collection-entry-item">
+                      <span className="entry-title">
+                        {entry.title || entry.entry_uid}
+                      </span>
+                      <span className="muted" style={{ fontSize: '0.8em' }}>
+                        {entry.source_kind}
+                      </span>
+                    </li>
+                  ))}
+                </ul>
+              )
+            ) : null}
+          </div>
+        )}
+      </div>
+
+      <details className="create-collection-form" style={{ marginTop: '1.5rem' }}>
+        <summary style={{ cursor: 'pointer', fontWeight: 600 }}>Create collection</summary>
+        <form onSubmit={handleCreate} style={{ marginTop: '0.75rem', display: 'flex', flexDirection: 'column', gap: '0.5rem', maxWidth: 400 }}>
+          <label>
+            Name
+            <input
+              className="form-input"
+              type="text"
+              value={newName}
+              onChange={e => { setNewName(e.target.value); if (!newSlug) setNewSlug(e.target.value.toLowerCase().replace(/[^a-z0-9]+/g, '-').replace(/^-|-$/g, '')) }}
+              placeholder="My Collection"
+              required
+            />
+          </label>
+          <label>
+            Slug
+            <input
+              className="form-input"
+              type="text"
+              value={newSlug}
+              onChange={e => setNewSlug(e.target.value)}
+              placeholder="my-collection"
+              required
+            />
+          </label>
+          <label>
+            Default visibility
+            <select className="form-input" value={newVis} onChange={e => setNewVis(Number(e.target.value))}>
+              <option value={0}>Private (admin/owner only)</option>
+              <option value={2}>Users only (logged in)</option>
+              <option value={3}>Public</option>
+            </select>
+          </label>
+          {createError && <div className="muted" style={{ color: 'var(--accent)' }}>{createError}</div>}
+          <button className="btn" type="submit" disabled={creating}>
+            {creating ? 'Creating…' : 'Create'}
+          </button>
+        </form>
+      </details>
+    </div>
+  )
+}
diff --git a/frontend/src/components/ContextRail.jsx b/frontend/src/components/ContextRail.jsx
index ff497fc..b94c6a5 100644
--- a/frontend/src/components/ContextRail.jsx
+++ b/frontend/src/components/ContextRail.jsx
@@ -1,11 +1,12 @@
 import { useState, useEffect, useRef } from 'react'
-import { fetchEntryDetail, fetchEntryTags, assignTag, removeTag } from '../api'
+import { fetchEntryDetail, fetchEntryTags, assignTag, removeTag, listEntryCollections } from '../api'
 import { formatTimestamp, formatBytes, valueText } from '../utils'
 
 export default function ContextRail({ archiveId, selectedEntry, onTagFilterSet, tagNodes, onTagsRefresh }) {
   const [detail, setDetail] = useState(null)
   const [tags, setTags] = useState([])
   const [assignInput, setAssignInput] = useState('')
+  const [entryCollections, setEntryCollections] = useState([])
   const [assignError, setAssignError] = useState('')
   const selectSeqRef = useRef(0)
 
@@ -13,6 +14,7 @@ export default function ContextRail({ archiveId, selectedEntry, onTagFilterSet,
     if (!selectedEntry || !archiveId) {
       setDetail(null)
       setTags([])
+      setEntryCollections([])
       return
     }
     const seq = ++selectSeqRef.current
@@ -21,10 +23,12 @@ export default function ContextRail({ archiveId, selectedEntry, onTagFilterSet,
     Promise.all([
       fetchEntryDetail(archiveId, selectedEntry.entry_uid),
       fetchEntryTags(archiveId, selectedEntry.entry_uid),
-    ]).then(([det, tgs]) => {
+      listEntryCollections(archiveId, selectedEntry.entry_uid),
+    ]).then(([det, tgs, ecs]) => {
       if (seq !== selectSeqRef.current) return
       setDetail(det)
       setTags(tgs)
+      setEntryCollections(ecs)
     }).catch(() => {})
   }, [selectedEntry, archiveId])
 
@@ -156,6 +160,19 @@ export default function ContextRail({ archiveId, selectedEntry, onTagFilterSet,
               </div>
             )}
           </div>
+          {selectedEntry && entryCollections.length > 0 && (
+            <div className="rail-section">
+              <div className="rail-section-heading">Collections</div>
+              {entryCollections.map(c => (
+                <div key={c.collection_uid} className="rail-item">
+                  <span className="rail-label">{c.collection_uid}</span>:{' '}
+                  <span className="muted">
+                    {{ 0: 'Private', 1: 'Public', 2: 'Users only', 3: 'Public' }[c.visibility_bits] ?? `bits:${c.visibility_bits}`}
+                  </span>
+                </div>
+              ))}
+            </div>
+          )}
         </>
       )}
     </aside>
diff --git a/frontend/src/components/Topbar.jsx b/frontend/src/components/Topbar.jsx
index fb55ea7..bf6ced4 100644
--- a/frontend/src/components/Topbar.jsx
+++ b/frontend/src/components/Topbar.jsx
@@ -21,7 +21,7 @@ export default function Topbar({ archives, archiveId, onArchiveChange, view, onV
         {archives.map(a => <option key={a.id} value={a.id}>{a.label}</option>)}
       </select>
       <nav className="nav" aria-label="Primary">
-        {['archive', 'runs', 'admin', 'tags'].map(name => (
+        {['archive', 'runs', 'admin', 'tags', 'collections'].map(name => (
           <button key={name} className={`nav-link${view === name ? ' is-active' : ''}`}
             onClick={() => onViewChange(name)}>
             {name.charAt(0).toUpperCase() + name.slice(1)}