diff --git a/src/components/admin/AdminUsersModal.tsx b/src/components/admin/AdminUsersModal.tsx
new file mode 100644
index 0000000..1d4fbad
--- /dev/null
+++ b/src/components/admin/AdminUsersModal.tsx
@@ -0,0 +1,137 @@
+import { useEffect, useState } from 'react'
+import type { AdminUserSummary, UserRole } from '../../data/AdminUserRepository'
+import { useAdminUserStore } from '../../state/adminUserStore'
+import { useAuthStore } from '../../state/authStore'
+import Modal from '../common/Modal'
+
+const ROLE_OPTIONS: UserRole[] = ['regular', 'admin', 'super_admin']
+
+function formatDate(iso: string): string {
+  return new Date(iso).toLocaleDateString(undefined, { dateStyle: 'medium' })
+}
+
+function isBanned(user: AdminUserSummary): boolean {
+  return !!user.bannedUntil && new Date(user.bannedUntil).getTime() > Date.now()
+}
+
+export default function AdminUsersModal({ onClose }: { onClose: () => void }) {
+  const currentUserId = useAuthStore((s) => s.userId)
+  const users = useAdminUserStore((s) => s.users)
+  const loadUsers = useAdminUserStore((s) => s.loadUsers)
+  const updateRole = useAdminUserStore((s) => s.updateRole)
+  const banUser = useAdminUserStore((s) => s.banUser)
+  const unbanUser = useAdminUserStore((s) => s.unbanUser)
+  const deleteUser = useAdminUserStore((s) => s.deleteUser)
+  const [busyId, setBusyId] = useState<string | null>(null)
+  const [error, setError] = useState<string | null>(null)
+
+  useEffect(() => {
+    loadUsers()
+  }, [loadUsers])
+
+  const runAction = async (userId: string, action: () => Promise<void>) => {
+    setError(null)
+    setBusyId(userId)
+    try {
+      await action()
+    } catch (err) {
+      setError(err instanceof Error ? err.message : 'Something went wrong.')
+    } finally {
+      setBusyId(null)
+    }
+  }
+
+  const handleRoleChange = (user: AdminUserSummary, role: UserRole) => {
+    if (user.id === currentUserId && role !== 'super_admin') {
+      const confirmed = window.confirm(
+        `Change your own role to "${role}"? You'll lose Super Admin access immediately — another Super Admin (or direct DB access) would be needed to undo this.`,
+      )
+      if (!confirmed) return
+    }
+    runAction(user.id, () => updateRole(user.id, role))
+  }
+
+  const handleBanToggle = (user: AdminUserSummary) => {
+    const banned = isBanned(user)
+    const confirmed = window.confirm(
+      banned ? `Unban "${user.username}"? They'll be able to sign in again.` : `Ban "${user.username}"? This blocks sign-in but keeps their data intact — reversible.`,
+    )
+    if (!confirmed) return
+    runAction(user.id, () => (banned ? unbanUser(user.id) : banUser(user.id)))
+  }
+
+  const handleDelete = (user: AdminUserSummary) => {
+    const confirmed = window.confirm(
+      `Permanently delete "${user.username}"? This deletes their account AND all their diagrams and private catalog entries. This cannot be undone.`,
+    )
+    if (!confirmed) return
+    runAction(user.id, () => deleteUser(user.id))
+  }
+
+  return (
+    <Modal title="Manage Users" onClose={onClose} width="max-w-2xl">
+      {error && <p className="mb-2 rounded bg-red-50 px-2 py-1.5 text-xs text-red-700">{error}</p>}
+      <div className="space-y-1.5">
+        {users.map((user) => {
+          const busy = busyId === user.id
+          const self = user.id === currentUserId
+          const banned = isBanned(user)
+          return (
+            <div key={user.id} className="flex items-center justify-between gap-2 rounded border border-slate-200 bg-white px-2.5 py-1.5 text-xs">
+              <div className="min-w-0">
+                <div className="flex items-center gap-1.5">
+                  <span className="font-medium text-slate-700">{user.username}</span>
+                  {self && (
+                    <span className="rounded bg-indigo-50 px-1.5 py-0.5 text-[10px] font-medium text-indigo-600">You</span>
+                  )}
+                  {banned && (
+                    <span className="rounded bg-red-50 px-1.5 py-0.5 text-[10px] font-medium text-red-600">Banned</span>
+                  )}
+                </div>
+                <div className="truncate text-[10px] text-slate-400">
+                  {user.email} · joined {formatDate(user.createdAt)}
+                </div>
+              </div>
+              <div className="flex shrink-0 items-center gap-1.5">
+                <select
+                  value={user.role}
+                  disabled={busy}
+                  onChange={(e) => handleRoleChange(user, e.target.value as UserRole)}
+                  className="rounded border border-slate-300 px-1 py-1 text-[11px] disabled:opacity-50"
+                >
+                  {ROLE_OPTIONS.map((r) => (
+                    <option key={r} value={r}>
+                      {r}
+                    </option>
+                  ))}
+                </select>
+                <button
+                  onClick={() => handleBanToggle(user)}
+                  disabled={busy || self}
+                  title={self ? "You can't ban your own account" : undefined}
+                  className="rounded bg-slate-100 px-2 py-1 text-[11px] font-medium text-slate-600 hover:bg-amber-50 hover:text-amber-700 disabled:cursor-not-allowed disabled:opacity-40"
+                >
+                  {banned ? 'Unban' : 'Ban'}
+                </button>
+                <button
+                  onClick={() => handleDelete(user)}
+                  disabled={busy || self}
+                  title={self ? "You can't delete your own account" : undefined}
+                  className="rounded bg-slate-100 px-2 py-1 text-[11px] font-medium text-slate-600 hover:bg-red-50 hover:text-red-600 disabled:cursor-not-allowed disabled:opacity-40"
+                >
+                  Delete
+                </button>
+              </div>
+            </div>
+          )
+        })}
+        {users.length === 0 && <p className="py-2 text-center text-xs italic text-slate-400">No users found.</p>}
+      </div>
+      <div className="mt-4 flex justify-end border-t border-slate-100 pt-3">
+        <button onClick={onClose} className="rounded px-3 py-1.5 text-xs text-slate-600 hover:bg-slate-100">
+          Close
+        </button>
+      </div>
+    </Modal>
+  )
+}
diff --git a/src/components/layout/TopBar.tsx b/src/components/layout/TopBar.tsx
index c2d1733..5576233 100644
--- a/src/components/layout/TopBar.tsx
+++ b/src/components/layout/TopBar.tsx
@@ -5,6 +5,7 @@ import { useAdminReviewStore } from '../../state/adminReviewStore'
 import { useAuthStore } from '../../state/authStore'
 import { useProjectStore } from '../../state/projectStore'
 import { useSubmissionStore } from '../../state/submissionStore'
+import AdminUsersModal from '../admin/AdminUsersModal'
 import AdminReviewModal from '../submissions/AdminReviewModal'
 import MySubmissionsModal from '../submissions/MySubmissionsModal'
 import DiagramManagerModal from './DiagramManagerModal'
@@ -37,11 +38,13 @@ export default function TopBar() {
   const username = useAuthStore((s) => s.username)
   const role = useAuthStore((s) => s.role)
   const isAdmin = role === 'admin' || role === 'super_admin'
+  const isSuperAdmin = role === 'super_admin'
   const adminPendingCount = useAdminReviewStore((s) => s.allSubmissions.filter((sub) => sub.status === 'pending').length)
   const fileInputRef = useRef<HTMLInputElement>(null)
   const [diagramManagerOpen, setDiagramManagerOpen] = useState(false)
   const [submissionsOpen, setSubmissionsOpen] = useState(false)
   const [adminReviewOpen, setAdminReviewOpen] = useState(false)
+  const [adminUsersOpen, setAdminUsersOpen] = useState(false)
 
   const pendingSubmissionCount = useMemo(
     () => mySubmissions.filter((s) => s.status === 'pending').length,
@@ -121,6 +124,14 @@ export default function TopBar() {
             )}
           </button>
         )}
+        {isSuperAdmin && (
+          <button
+            onClick={() => setAdminUsersOpen(true)}
+            className="rounded px-2.5 py-1.5 text-xs text-slate-600 hover:bg-slate-100"
+          >
+            Manage Users
+          </button>
+        )}
         <button onClick={handleImportClick} className="rounded px-2.5 py-1.5 text-xs text-slate-600 hover:bg-slate-100">
           Import
         </button>
@@ -142,6 +153,7 @@ export default function TopBar() {
       {diagramManagerOpen && <DiagramManagerModal onClose={() => setDiagramManagerOpen(false)} />}
       {submissionsOpen && <MySubmissionsModal onClose={() => setSubmissionsOpen(false)} />}
       {adminReviewOpen && <AdminReviewModal onClose={() => setAdminReviewOpen(false)} />}
+      {adminUsersOpen && <AdminUsersModal onClose={() => setAdminUsersOpen(false)} />}
     </header>
   )
 }
diff --git a/src/components/palette/CableTypeManager.tsx b/src/components/palette/CableTypeManager.tsx
index fd3bf84..b39bfc8 100644
--- a/src/components/palette/CableTypeManager.tsx
+++ b/src/components/palette/CableTypeManager.tsx
@@ -2,6 +2,8 @@ import { useMemo, useState } from 'react'
 import { allCableTypes, allPortTypes } from '../../domain/project'
 import type { CableType, PortType } from '../../domain/types'
 import { cableTypeToRow } from '../../data/catalogRowMapping'
+import { useAdminReviewStore } from '../../state/adminReviewStore'
+import { useAuthStore } from '../../state/authStore'
 import { useCatalogStore } from '../../state/catalogStore'
 import { useSubmissionStore } from '../../state/submissionStore'
 import { resolveCableTypeFields, type CableTypeFormFields } from './cableTypeFormFields'
@@ -129,11 +131,17 @@ export default function CableTypesPanel() {
   const catalog = useCatalogStore((s) => s.catalog)
   const addCustomCableType = useCatalogStore((s) => s.addCustomCableType)
   const updateCustomCableType = useCatalogStore((s) => s.updateCustomCableType)
+  const adminUpdateCableType = useCatalogStore((s) => s.adminUpdateCableType)
+  const adminUnpublish = useCatalogStore((s) => s.adminUnpublish)
   const mySubmissions = useSubmissionStore((s) => s.mySubmissions)
   const submitForReview = useSubmissionStore((s) => s.submitForReview)
+  const getUsageImpact = useAdminReviewStore((s) => s.getUsageImpact)
+  const role = useAuthStore((s) => s.role)
+  const isAdmin = role === 'admin' || role === 'super_admin'
   const [creating, setCreating] = useState(false)
   const [editingId, setEditingId] = useState<string | null>(null)
   const [suggestingId, setSuggestingId] = useState<string | null>(null)
+  const [adminEditingId, setAdminEditingId] = useState<string | null>(null)
 
   const portTypes = useMemo(
     () => [...allPortTypes(catalog)].sort((a, b) => a.name.localeCompare(b.name)),
@@ -185,6 +193,24 @@ export default function CableTypesPanel() {
     setSuggestingId(null)
   }
 
+  const handleAdminSave = (id: string, fields: CableTypeFormFields) => {
+    const resolved = resolveCableTypeFields(fields, portTypes)
+    if (!resolved) return
+    adminUpdateCableType(id, resolved)
+    setAdminEditingId(null)
+  }
+
+  const handleUnpublish = async (ct: CableType) => {
+    const impact = await getUsageImpact('cable_type', ct.id)
+    const impactNote =
+      impact.diagramCount > 0
+        ? `\n\nUsed in ${impact.diagramCount} diagram${impact.diagramCount === 1 ? '' : 's'}: ${impact.sample.map((s) => `${s.name} (${s.ownerUsername})`).join(', ')}${impact.diagramCount > impact.sample.length ? ', …' : ''}. Existing diagrams keep working — this only removes it from new use.`
+        : '\n\nNot currently used in any diagram.'
+    const confirmed = window.confirm(`Unpublish "${ct.name}" from the public catalog?${impactNote}`)
+    if (!confirmed) return
+    adminUnpublish('cable_type', ct.id)
+  }
+
   return (
     <div className="space-y-4">
       <div>
@@ -263,22 +289,52 @@ export default function CableTypesPanel() {
           Built-in ({builtInTypes.length})
         </h4>
         <div className="max-h-64 space-y-1 overflow-y-auto rounded border border-slate-200 p-1.5">
-          {builtInTypes.map((ct) =>
-            suggestingId === ct.id ? (
-              <div key={ct.id} className="mb-1.5">
-                <CableTypeForm
-                  initial={ct}
-                  portTypes={portTypes}
-                  onCancel={() => setSuggestingId(null)}
-                  onSave={(fields) => handleSuggestEdit(ct.id, fields)}
-                />
-              </div>
-            ) : (
+          {builtInTypes.map((ct) => {
+            if (isAdmin && adminEditingId === ct.id) {
+              return (
+                <div key={ct.id} className="mb-1.5">
+                  <CableTypeForm
+                    initial={ct}
+                    portTypes={portTypes}
+                    onCancel={() => setAdminEditingId(null)}
+                    onSave={(fields) => handleAdminSave(ct.id, fields)}
+                  />
+                </div>
+              )
+            }
+            if (!isAdmin && suggestingId === ct.id) {
+              return (
+                <div key={ct.id} className="mb-1.5">
+                  <CableTypeForm
+                    initial={ct}
+                    portTypes={portTypes}
+                    onCancel={() => setSuggestingId(null)}
+                    onSave={(fields) => handleSuggestEdit(ct.id, fields)}
+                  />
+                </div>
+              )
+            }
+            return (
               <div key={ct.id} className="flex items-center justify-between gap-2 px-1 py-0.5 text-[11px] text-slate-500">
                 <span className="min-w-0 truncate">
                   {ct.name} <span className="text-slate-400">· {describeEnds(ct)}</span>
                 </span>
-                {pendingEntityIds.has(ct.id) ? (
+                {isAdmin ? (
+                  <div className="flex shrink-0 items-center gap-1">
+                    <button
+                      onClick={() => setAdminEditingId(ct.id)}
+                      className="rounded bg-slate-100 px-1.5 py-0.5 text-[10px] font-medium text-slate-500 hover:bg-indigo-100 hover:text-indigo-700"
+                    >
+                      Edit
+                    </button>
+                    <button
+                      onClick={() => handleUnpublish(ct)}
+                      className="rounded bg-slate-100 px-1.5 py-0.5 text-[10px] font-medium text-slate-500 hover:bg-red-50 hover:text-red-600"
+                    >
+                      Unpublish
+                    </button>
+                  </div>
+                ) : pendingEntityIds.has(ct.id) ? (
                   <span className="shrink-0 rounded bg-amber-50 px-1.5 py-0.5 text-[10px] font-medium text-amber-600">
                     Edit pending review
                   </span>
@@ -291,11 +347,13 @@ export default function CableTypesPanel() {
                   </button>
                 )}
               </div>
-            ),
-          )}
+            )
+          })}
         </div>
         <p className="mt-1 text-[10px] text-slate-400">
-          Built-in cable types can't be edited directly — "Suggest edit" sends a proposed change to Admins for review.
+          {isAdmin
+            ? 'As an Admin, you can edit or unpublish public cable types directly.'
+            : 'Built-in cable types can\'t be edited directly — "Suggest edit" sends a proposed change to Admins for review.'}
         </p>
       </div>
     </div>
diff --git a/src/components/palette/DevicePalette.tsx b/src/components/palette/DevicePalette.tsx
index 8bbc7c8..2755554 100644
--- a/src/components/palette/DevicePalette.tsx
+++ b/src/components/palette/DevicePalette.tsx
@@ -2,6 +2,8 @@ import { useMemo, useState } from 'react'
 import { deviceTemplateToRow } from '../../data/catalogRowMapping'
 import { allDeviceCategories, allDeviceTemplates, hiddenDeviceTemplates } from '../../domain/project'
 import type { DeviceTemplate } from '../../domain/types'
+import { useAdminReviewStore } from '../../state/adminReviewStore'
+import { useAuthStore } from '../../state/authStore'
 import { useCatalogStore } from '../../state/catalogStore'
 import { useProjectStore } from '../../state/projectStore'
 import { useSubmissionStore } from '../../state/submissionStore'
@@ -10,7 +12,11 @@ import Chevron from '../common/Chevron'
 import ConnectorLibraryModal from './ConnectorLibraryModal'
 import DeviceTemplateEditor from './DeviceTemplateEditor'
 
-type EditorTarget = { mode: 'new' } | { mode: 'edit'; template: DeviceTemplate } | { mode: 'suggestEdit'; template: DeviceTemplate }
+type EditorTarget =
+  | { mode: 'new' }
+  | { mode: 'edit'; template: DeviceTemplate }
+  | { mode: 'suggestEdit'; template: DeviceTemplate }
+  | { mode: 'adminEdit'; template: DeviceTemplate }
 
 export default function DevicePalette() {
   const project = useProjectStore((s) => s.project)
@@ -20,8 +26,12 @@ export default function DevicePalette() {
   const removeCustomDeviceTemplate = useCatalogStore((s) => s.removeCustomDeviceTemplate)
   const hidePublicDeviceTemplate = useCatalogStore((s) => s.hidePublicDeviceTemplate)
   const restorePublicDeviceTemplate = useCatalogStore((s) => s.restorePublicDeviceTemplate)
+  const adminUnpublish = useCatalogStore((s) => s.adminUnpublish)
   const mySubmissions = useSubmissionStore((s) => s.mySubmissions)
   const submitForReview = useSubmissionStore((s) => s.submitForReview)
+  const getUsageImpact = useAdminReviewStore((s) => s.getUsageImpact)
+  const role = useAuthStore((s) => s.role)
+  const isAdmin = role === 'admin' || role === 'super_admin'
   const [editorTarget, setEditorTarget] = useState<EditorTarget | null>(null)
   const [portTypesOpen, setPortTypesOpen] = useState(false)
   const [hiddenListOpen, setHiddenListOpen] = useState(false)
@@ -99,6 +109,17 @@ export default function DevicePalette() {
     submitForReview('device_template', template.id, deviceTemplateToRow(template))
   }
 
+  const handleUnpublish = async (template: DeviceTemplate) => {
+    const impact = await getUsageImpact('device_template', template.id)
+    const impactNote =
+      impact.diagramCount > 0
+        ? `\n\nUsed in ${impact.diagramCount} diagram${impact.diagramCount === 1 ? '' : 's'}: ${impact.sample.map((s) => `${s.name} (${s.ownerUsername})`).join(', ')}${impact.diagramCount > impact.sample.length ? ', …' : ''}. Existing diagrams keep working — this only removes it from new use.`
+        : '\n\nNot currently used in any diagram.'
+    const confirmed = window.confirm(`Unpublish "${template.name}" from the public catalog?${impactNote}`)
+    if (!confirmed) return
+    adminUnpublish('device_template', template.id)
+  }
+
   return (
     <aside className="flex h-full w-64 shrink-0 flex-col border-r border-slate-200 bg-slate-50">
       <div className="flex items-center justify-between border-b border-slate-200 px-3 py-2">
@@ -169,6 +190,23 @@ export default function DevicePalette() {
                             >
                               ⇪
                             </button>
+                          ) : isAdmin ? (
+                            <>
+                              <button
+                                onClick={() => setEditorTarget({ mode: 'adminEdit', template })}
+                                title="Edit this public device directly"
+                                className="rounded bg-slate-100 px-1.5 py-0.5 text-slate-500 hover:bg-indigo-100 hover:text-indigo-700"
+                              >
+                                ✎
+                              </button>
+                              <button
+                                onClick={() => handleUnpublish(template)}
+                                title="Unpublish from the public catalog"
+                                className="rounded bg-slate-100 px-1.5 py-0.5 text-slate-500 hover:bg-red-50 hover:text-red-600"
+                              >
+                                ⛔
+                              </button>
+                            </>
                           ) : (
                             <button
                               onClick={() => setEditorTarget({ mode: 'suggestEdit', template })}
@@ -243,6 +281,7 @@ export default function DevicePalette() {
         <DeviceTemplateEditor
           template={editorTarget.mode === 'new' ? undefined : editorTarget.template}
           submissionMode={editorTarget.mode === 'suggestEdit'}
+          adminMode={editorTarget.mode === 'adminEdit'}
           onClose={() => setEditorTarget(null)}
           onSaved={(categoryId) => expandCategory(categoryId)}
         />
diff --git a/src/components/palette/DeviceTemplateEditor.tsx b/src/components/palette/DeviceTemplateEditor.tsx
index 4e3db6c..5ecb5f5 100644
--- a/src/components/palette/DeviceTemplateEditor.tsx
+++ b/src/components/palette/DeviceTemplateEditor.tsx
@@ -24,6 +24,7 @@ function nextDraftKey() {
 export default function DeviceTemplateEditor({
   template,
   submissionMode = false,
+  adminMode = false,
   resubmitId,
   onClose,
   onSaved,
@@ -34,10 +35,14 @@ export default function DeviceTemplateEditor({
    *  a suggested edit for Admin review instead of mutating it directly
    *  (which RLS wouldn't allow anyway). */
   submissionMode?: boolean
+  /** When true, saves directly to the public entry (organized-ideas.md §6:
+   *  Admin/Super-Admin can CRUD public entries without going through the
+   *  submission workflow). Takes precedence over `submissionMode`. */
+  adminMode?: boolean
   /** When set, saving revises this existing submission (of your own,
    *  pending or rejected) instead of creating a new one — see
    *  MySubmissionsModal's "Edit & resubmit". Takes precedence over
-   *  `submissionMode` if both are somehow set. */
+   *  `submissionMode`/`adminMode` if somehow more than one is set. */
   resubmitId?: string
   onClose: () => void
   /** Called with the template's category id right before closing, so the
@@ -47,6 +52,7 @@ export default function DeviceTemplateEditor({
   const catalog = useCatalogStore((s) => s.catalog)
   const addCustomDeviceTemplate = useCatalogStore((s) => s.addCustomDeviceTemplate)
   const updateCustomDeviceTemplate = useCatalogStore((s) => s.updateCustomDeviceTemplate)
+  const adminUpdateDeviceTemplate = useCatalogStore((s) => s.adminUpdateDeviceTemplate)
   const addCustomPortType = useCatalogStore((s) => s.addCustomPortType)
   const submitForReview = useSubmissionStore((s) => s.submitForReview)
   const resubmit = useSubmissionStore((s) => s.resubmit)
@@ -141,6 +147,8 @@ export default function DeviceTemplateEditor({
     }
     if (resubmitId) {
       resubmit(resubmitId, deviceTemplateToRow(fields))
+    } else if (adminMode && template) {
+      adminUpdateDeviceTemplate(template.id, fields)
     } else if (submissionMode && template) {
       submitForReview('device_template', template.id, deviceTemplateToRow(fields))
     } else if (template) {
@@ -154,7 +162,17 @@ export default function DeviceTemplateEditor({
 
   return (
     <Modal
-      title={resubmitId ? 'Revise Submission' : submissionMode ? 'Suggest an Edit' : template ? 'Edit Custom Device' : 'New Custom Device'}
+      title={
+        resubmitId
+          ? 'Revise Submission'
+          : adminMode
+            ? 'Edit Public Device'
+            : submissionMode
+              ? 'Suggest an Edit'
+              : template
+                ? 'Edit Custom Device'
+                : 'New Custom Device'
+      }
       onClose={onClose}
       width="max-w-xl"
     >
@@ -350,7 +368,15 @@ export default function DeviceTemplateEditor({
             disabled={!canSave}
             className="rounded bg-indigo-600 px-3 py-1.5 text-xs font-medium text-white hover:bg-indigo-500 disabled:cursor-not-allowed disabled:opacity-40"
           >
-            {resubmitId ? 'Resubmit' : submissionMode ? 'Submit for review' : template ? 'Save changes' : 'Save device'}
+            {resubmitId
+              ? 'Resubmit'
+              : adminMode
+                ? 'Save changes'
+                : submissionMode
+                  ? 'Submit for review'
+                  : template
+                    ? 'Save changes'
+                    : 'Save device'}
           </button>
         </div>
       </div>
diff --git a/src/components/palette/PortTypeManager.tsx b/src/components/palette/PortTypeManager.tsx
index 02f732e..6ae6a36 100644
--- a/src/components/palette/PortTypeManager.tsx
+++ b/src/components/palette/PortTypeManager.tsx
@@ -3,6 +3,8 @@ import { PORT_CATEGORIES } from '../../domain/constants'
 import { allPortTypes, expandCompatibleFamilyIds } from '../../domain/project'
 import type { PortType } from '../../domain/types'
 import { portTypeToRow } from '../../data/catalogRowMapping'
+import { useAdminReviewStore } from '../../state/adminReviewStore'
+import { useAuthStore } from '../../state/authStore'
 import { useCatalogStore } from '../../state/catalogStore'
 import { useSubmissionStore } from '../../state/submissionStore'
 
@@ -105,10 +107,16 @@ export function PortTypeForm({
 export default function PortTypesPanel() {
   const catalog = useCatalogStore((s) => s.catalog)
   const updateCustomPortType = useCatalogStore((s) => s.updateCustomPortType)
+  const adminUpdatePortType = useCatalogStore((s) => s.adminUpdatePortType)
+  const adminUnpublish = useCatalogStore((s) => s.adminUnpublish)
   const mySubmissions = useSubmissionStore((s) => s.mySubmissions)
   const submitForReview = useSubmissionStore((s) => s.submitForReview)
+  const getUsageImpact = useAdminReviewStore((s) => s.getUsageImpact)
+  const role = useAuthStore((s) => s.role)
+  const isAdmin = role === 'admin' || role === 'super_admin'
   const [editingId, setEditingId] = useState<string | null>(null)
   const [suggestingId, setSuggestingId] = useState<string | null>(null)
+  const [adminEditingId, setAdminEditingId] = useState<string | null>(null)
 
   const allTypes = useMemo(
     () => [...allPortTypes(catalog)].sort((a, b) => a.name.localeCompare(b.name)),
@@ -144,6 +152,22 @@ export default function PortTypesPanel() {
     setSuggestingId(null)
   }
 
+  const handleAdminSave = (id: string, fields: Omit<PortType, 'id' | 'custom'>) => {
+    adminUpdatePortType(id, fields)
+    setAdminEditingId(null)
+  }
+
+  const handleUnpublish = async (pt: PortType) => {
+    const impact = await getUsageImpact('port_type', pt.id)
+    const impactNote =
+      impact.diagramCount > 0
+        ? `\n\nUsed in ${impact.diagramCount} diagram${impact.diagramCount === 1 ? '' : 's'}: ${impact.sample.map((s) => `${s.name} (${s.ownerUsername})`).join(', ')}${impact.diagramCount > impact.sample.length ? ', …' : ''}. Existing diagrams keep working — this only removes it from new use.`
+        : '\n\nNot currently used in any diagram.'
+    const confirmed = window.confirm(`Unpublish "${pt.name}" from the public catalog?${impactNote}`)
+    if (!confirmed) return
+    adminUnpublish('port_type', pt.id)
+  }
+
   return (
     <div className="space-y-4">
       <div>
@@ -213,16 +237,30 @@ export default function PortTypesPanel() {
           Built-in ({builtInTypes.length})
         </h4>
         <div className="max-h-64 space-y-1 overflow-y-auto rounded border border-slate-200 p-1.5">
-          {builtInTypes.map((pt) =>
-            suggestingId === pt.id ? (
-              <PortTypeForm
-                key={pt.id}
-                portType={pt}
-                allTypes={allTypes}
-                onCancel={() => setSuggestingId(null)}
-                onSave={(fields) => handleSuggestEdit(pt.id, fields)}
-              />
-            ) : (
+          {builtInTypes.map((pt) => {
+            if (isAdmin && adminEditingId === pt.id) {
+              return (
+                <PortTypeForm
+                  key={pt.id}
+                  portType={pt}
+                  allTypes={allTypes}
+                  onCancel={() => setAdminEditingId(null)}
+                  onSave={(fields) => handleAdminSave(pt.id, fields)}
+                />
+              )
+            }
+            if (!isAdmin && suggestingId === pt.id) {
+              return (
+                <PortTypeForm
+                  key={pt.id}
+                  portType={pt}
+                  allTypes={allTypes}
+                  onCancel={() => setSuggestingId(null)}
+                  onSave={(fields) => handleSuggestEdit(pt.id, fields)}
+                />
+              )
+            }
+            return (
               <div key={pt.id} className="flex items-center justify-between gap-2 px-1 py-0.5 text-[11px] text-slate-500">
                 <span className="min-w-0 truncate">
                   {pt.name}
@@ -230,7 +268,22 @@ export default function PortTypesPanel() {
                     <span className="text-slate-400"> · also fits: {describeCompatibility(pt)}</span>
                   )}
                 </span>
-                {pendingEntityIds.has(pt.id) ? (
+                {isAdmin ? (
+                  <div className="flex shrink-0 items-center gap-1">
+                    <button
+                      onClick={() => setAdminEditingId(pt.id)}
+                      className="rounded bg-slate-100 px-1.5 py-0.5 text-[10px] font-medium text-slate-500 hover:bg-indigo-100 hover:text-indigo-700"
+                    >
+                      Edit
+                    </button>
+                    <button
+                      onClick={() => handleUnpublish(pt)}
+                      className="rounded bg-slate-100 px-1.5 py-0.5 text-[10px] font-medium text-slate-500 hover:bg-red-50 hover:text-red-600"
+                    >
+                      Unpublish
+                    </button>
+                  </div>
+                ) : pendingEntityIds.has(pt.id) ? (
                   <span className="shrink-0 rounded bg-amber-50 px-1.5 py-0.5 text-[10px] font-medium text-amber-600">
                     Edit pending review
                   </span>
@@ -243,11 +296,13 @@ export default function PortTypesPanel() {
                   </button>
                 )}
               </div>
-            ),
-          )}
+            )
+          })}
         </div>
         <p className="mt-1 text-[10px] text-slate-400">
-          Built-in connector types can't be edited directly — "Suggest edit" sends a proposed change to Admins for review.
+          {isAdmin
+            ? 'As an Admin, you can edit or unpublish public connector types directly.'
+            : 'Built-in connector types can\'t be edited directly — "Suggest edit" sends a proposed change to Admins for review.'}
         </p>
       </div>
     </div>
diff --git a/src/data/AdminUserRepository.ts b/src/data/AdminUserRepository.ts
new file mode 100644
index 0000000..071035f
--- /dev/null
+++ b/src/data/AdminUserRepository.ts
@@ -0,0 +1,32 @@
+/** A user's role — mirrors `profiles.role`'s check constraint. Defined here
+ *  (data layer) rather than in state/authStore.ts so both that store and
+ *  this repository share one definition without state importing from data
+ *  in the wrong direction. */
+export type UserRole = 'regular' | 'admin' | 'super_admin'
+
+export interface AdminUserSummary {
+  id: string
+  username: string
+  email: string
+  role: UserRole
+  /** Set (a future timestamp) while banned; undefined otherwise. */
+  bannedUntil?: string
+  createdAt: string
+}
+
+/** Storage abstraction for Super-Admin user management (organized-ideas.md
+ *  §6's "CRUD user accounts"). Listing and role changes are plain
+ *  RLS/privileged-function reads and writes; ban/unban/delete go through
+ *  the admin-user-action Edge Function since those specifically need
+ *  Supabase Auth's Admin API — see that function's own header comment for
+ *  why this can't just be another SQL function like the rest. */
+export interface AdminUserRepository {
+  listUsers(): Promise<AdminUserSummary[]>
+  updateRole(userId: string, role: UserRole): Promise<void>
+  /** Reversible — blocks login without touching the account's data. */
+  banUser(userId: string): Promise<void>
+  unbanUser(userId: string): Promise<void>
+  /** Irreversible — cascades to the user's profile, diagrams, and owned
+   *  private catalog entries via their existing foreign keys. */
+  deleteUser(userId: string): Promise<void>
+}
diff --git a/src/data/CatalogRepository.ts b/src/data/CatalogRepository.ts
index 2d7e3d2..8e6ba63 100644
--- a/src/data/CatalogRepository.ts
+++ b/src/data/CatalogRepository.ts
@@ -1,3 +1,4 @@
+import type { CatalogEntityType } from './SubmissionRepository'
 import type { Catalog, CableType, DeviceCategoryDef, DeviceTemplate, PortType } from '../domain/types'
 
 /**
@@ -7,10 +8,14 @@ import type { Catalog, CableType, DeviceCategoryDef, DeviceTemplate, PortType }
  * entries plus their own private ones); RLS does that filtering server-side,
  * so implementations don't need to filter client-side.
  *
- * Only covers the "read + manage your own private entries" surface for now.
- * Submitting a private entry for public review/promotion is a separate,
- * not-yet-built workflow (organized-ideas.md §3/§9) — these `add*`/`update*`
- * methods always create or edit is_public = false rows you own.
+ * The `add*`/`update*` methods always create or edit an `is_public = false`
+ * row you own — that's the regular-user "own private catalog" surface.
+ * Getting an entry into the public catalog otherwise goes through the
+ * submission/review workflow (organized-ideas.md §3), except for the
+ * `admin*` methods below: per §6's capability table, an Admin/Super-Admin
+ * can also CRUD public entries directly, without a submission — those
+ * bypass ownership entirely (RLS's `is_admin()` clause is what actually
+ * allows it) and only ever touch already-public rows.
  */
 export interface CatalogRepository {
   /** Everything visible to the current user: public entries plus their own private ones. */
@@ -27,4 +32,16 @@ export interface CatalogRepository {
   addDeviceTemplate(template: Omit<DeviceTemplate, 'id' | 'custom'>): Promise<DeviceTemplate>
   updateDeviceTemplate(id: string, patch: Partial<Omit<DeviceTemplate, 'id' | 'custom'>>): Promise<void>
   removeDeviceTemplate(id: string): Promise<void>
+
+  /** Admin/Super-Admin direct edit of an already-public port/cable/device
+   *  entry — same underlying write as approving a submission, minus the
+   *  submission. */
+  adminUpdatePortType(id: string, patch: Partial<Omit<PortType, 'id' | 'custom'>>): Promise<void>
+  adminUpdateCableType(id: string, patch: Partial<Omit<CableType, 'id' | 'custom'>>): Promise<void>
+  adminUpdateDeviceTemplate(id: string, patch: Partial<Omit<DeviceTemplate, 'id' | 'custom'>>): Promise<void>
+  /** Unpublishes a public entry (is_public -> false) rather than deleting
+   *  it — organized-ideas.md §3's "public catalog entries are never hard-
+   *  deleted, only hidden/unpublished". Existing diagrams that reference it
+   *  by id are unaffected; it just stops being offered for new use. */
+  adminUnpublish(entityType: CatalogEntityType, id: string): Promise<void>
 }
diff --git a/src/data/SupabaseAdminSubmissionRepository.ts b/src/data/SupabaseAdminSubmissionRepository.ts
index 825f654..17fb052 100644
--- a/src/data/SupabaseAdminSubmissionRepository.ts
+++ b/src/data/SupabaseAdminSubmissionRepository.ts
@@ -1,16 +1,10 @@
 import { v4 as uuid } from 'uuid'
 import type { AdminSubmissionRepository, UsageImpact, UsageImpactSample } from './AdminSubmissionRepository'
+import { CATALOG_TABLE_BY_ENTITY_TYPE } from './catalogRowMapping'
 import type { CatalogSubmission } from './SubmissionRepository'
 import { supabase } from './supabaseClient'
 import { toSubmission, type SubmissionRow } from './submissionRowMapping'
 
-const TABLE_BY_ENTITY_TYPE: Record<CatalogSubmission['entityType'], string> = {
-  device_template: 'device_templates',
-  port_type: 'port_types',
-  cable_type: 'cable_types',
-  device_category: 'device_categories',
-}
-
 interface ProposedDeviceTemplatePort {
   name: string
   direction: string
@@ -45,7 +39,7 @@ export class SupabaseAdminSubmissionRepository implements AdminSubmissionReposit
     // `ports` (device_template only) isn't a column on device_templates
     // itself; pull it out and replace device_template_ports separately.
     const { ports, ...rowPatch } = submission.proposedData as Record<string, unknown> & { ports?: ProposedDeviceTemplatePort[] }
-    const table = TABLE_BY_ENTITY_TYPE[submission.entityType]
+    const table = CATALOG_TABLE_BY_ENTITY_TYPE[submission.entityType]
     const { error } = await supabase
       .from(table)
       .update({ ...rowPatch, is_public: true, owner_id: null })
diff --git a/src/data/SupabaseAdminUserRepository.ts b/src/data/SupabaseAdminUserRepository.ts
new file mode 100644
index 0000000..84d4f2a
--- /dev/null
+++ b/src/data/SupabaseAdminUserRepository.ts
@@ -0,0 +1,73 @@
+import { FunctionsHttpError } from '@supabase/supabase-js'
+import type { AdminUserRepository, AdminUserSummary, UserRole } from './AdminUserRepository'
+import { supabase } from './supabaseClient'
+
+interface UserRow {
+  id: string
+  username: string
+  email: string
+  role: UserRole
+  banned_until: string | null
+  created_at: string
+}
+
+function toSummary(row: UserRow): AdminUserSummary {
+  return {
+    id: row.id,
+    username: row.username,
+    email: row.email,
+    role: row.role,
+    bannedUntil: row.banned_until ?? undefined,
+    createdAt: row.created_at,
+  }
+}
+
+type UserAction = 'ban' | 'unban' | 'delete'
+
+/** Backs the app with list_users_for_admin (read), a direct profiles.role
+ *  update, and the admin-user-action Edge Function (ban/unban/delete). */
+export class SupabaseAdminUserRepository implements AdminUserRepository {
+  async listUsers(): Promise<AdminUserSummary[]> {
+    const { data, error } = await supabase.rpc('list_users_for_admin')
+    if (error) {
+      console.error('Failed to list users from Supabase', error)
+      return []
+    }
+    return ((data ?? []) as UserRow[]).map(toSummary)
+  }
+
+  async updateRole(userId: string, role: UserRole): Promise<void> {
+    const { error } = await supabase.from('profiles').update({ role }).eq('id', userId)
+    if (error) console.error('Failed to update user role in Supabase', error)
+  }
+
+  private async invokeUserAction(action: UserAction, userId: string): Promise<void> {
+    const { error } = await supabase.functions.invoke('admin-user-action', { body: { action, userId } })
+    if (!error) return
+
+    // The function returns its actual reason (e.g. "Only a Super Admin can
+    // manage user accounts.") in the JSON body on a non-2xx response —
+    // surface that instead of supabase-js's generic "Edge Function
+    // returned a non-2xx status code" wrapper.
+    if (error instanceof FunctionsHttpError) {
+      const body = await error.context.json().catch(() => null)
+      const message = typeof body?.error === 'string' ? body.error : error.message
+      console.error(`Failed to ${action} user`, message)
+      throw new Error(message)
+    }
+    console.error(`Failed to ${action} user`, error)
+    throw error
+  }
+
+  banUser(userId: string): Promise<void> {
+    return this.invokeUserAction('ban', userId)
+  }
+
+  unbanUser(userId: string): Promise<void> {
+    return this.invokeUserAction('unban', userId)
+  }
+
+  deleteUser(userId: string): Promise<void> {
+    return this.invokeUserAction('delete', userId)
+  }
+}
diff --git a/src/data/SupabaseCatalogRepository.ts b/src/data/SupabaseCatalogRepository.ts
index 4a620a3..4f94306 100644
--- a/src/data/SupabaseCatalogRepository.ts
+++ b/src/data/SupabaseCatalogRepository.ts
@@ -1,7 +1,8 @@
 import { v4 as uuid } from 'uuid'
 import type { Catalog, CableType, DeviceCategoryDef, DeviceTemplate, Port, PortType } from '../domain/types'
-import { cableTypeToRow, deviceTemplateToRow, portTypeToRow } from './catalogRowMapping'
+import { CATALOG_TABLE_BY_ENTITY_TYPE, cableTypeToRow, deviceTemplateToRow, portTypeToRow } from './catalogRowMapping'
 import type { CatalogRepository } from './CatalogRepository'
+import type { CatalogEntityType } from './SubmissionRepository'
 import { supabase } from './supabaseClient'
 
 interface DeviceCategoryRow {
@@ -260,4 +261,28 @@ export class SupabaseCatalogRepository implements CatalogRepository {
     const { error } = await supabase.from('device_templates').delete().eq('id', id)
     if (error) console.error('Failed to remove device template from Supabase', error)
   }
+
+  // The update* methods above never check ownership themselves — RLS does,
+  // server-side, based on the caller's identity — so an Admin/Super-Admin
+  // direct edit of a public entry is *exactly* the same write, just
+  // permitted by a different branch of the same policy (`is_admin()`
+  // instead of "owns it and it's still private"). These are aliases, not
+  // separate logic, so the two paths can't drift apart.
+  adminUpdatePortType(id: string, patch: Partial<Omit<PortType, 'id' | 'custom'>>): Promise<void> {
+    return this.updatePortType(id, patch)
+  }
+
+  adminUpdateCableType(id: string, patch: Partial<Omit<CableType, 'id' | 'custom'>>): Promise<void> {
+    return this.updateCableType(id, patch)
+  }
+
+  adminUpdateDeviceTemplate(id: string, patch: Partial<Omit<DeviceTemplate, 'id' | 'custom'>>): Promise<void> {
+    return this.updateDeviceTemplate(id, patch)
+  }
+
+  async adminUnpublish(entityType: CatalogEntityType, id: string): Promise<void> {
+    const table = CATALOG_TABLE_BY_ENTITY_TYPE[entityType]
+    const { error } = await supabase.from(table).update({ is_public: false }).eq('id', id)
+    if (error) console.error('Failed to unpublish catalog entry in Supabase', error)
+  }
 }
diff --git a/src/data/catalogRowMapping.ts b/src/data/catalogRowMapping.ts
index 2324fec..74a13d7 100644
--- a/src/data/catalogRowMapping.ts
+++ b/src/data/catalogRowMapping.ts
@@ -1,3 +1,4 @@
+import type { CatalogEntityType } from './SubmissionRepository'
 import type { CableType, DeviceTemplate, PortType } from '../domain/types'
 
 /**
@@ -10,6 +11,16 @@ import type { CableType, DeviceTemplate, PortType } from '../domain/types'
  * step an Admin's approval action would otherwise have to duplicate.
  */
 
+/** Which table backs each catalog entity type — shared by
+ *  SupabaseAdminSubmissionRepository (approving into the right table) and
+ *  SupabaseCatalogRepository (direct Admin unpublish). */
+export const CATALOG_TABLE_BY_ENTITY_TYPE: Record<CatalogEntityType, string> = {
+  device_template: 'device_templates',
+  port_type: 'port_types',
+  cable_type: 'cable_types',
+  device_category: 'device_categories',
+}
+
 export function portTypeToRow(portType: Omit<PortType, 'id' | 'custom'>): Record<string, unknown> {
   return {
     name: portType.name,
diff --git a/src/state/adminUserStore.ts b/src/state/adminUserStore.ts
new file mode 100644
index 0000000..6496fa1
--- /dev/null
+++ b/src/state/adminUserStore.ts
@@ -0,0 +1,50 @@
+import { create } from 'zustand'
+import type { AdminUserRepository, AdminUserSummary, UserRole } from '../data/AdminUserRepository'
+import { SupabaseAdminUserRepository } from '../data/SupabaseAdminUserRepository'
+
+const repository: AdminUserRepository = new SupabaseAdminUserRepository()
+
+interface AdminUserStoreState {
+  users: AdminUserSummary[]
+  isLoaded: boolean
+
+  loadUsers: () => Promise<void>
+  updateRole: (userId: string, role: UserRole) => Promise<void>
+  banUser: (userId: string) => Promise<void>
+  unbanUser: (userId: string) => Promise<void>
+  deleteUser: (userId: string) => Promise<void>
+}
+
+export const useAdminUserStore = create<AdminUserStoreState>((set) => ({
+  users: [],
+  isLoaded: false,
+
+  loadUsers: async () => {
+    const users = await repository.listUsers()
+    set({ users, isLoaded: true })
+  },
+
+  updateRole: async (userId, role) => {
+    await repository.updateRole(userId, role)
+    set((state) => ({ users: state.users.map((u) => (u.id === userId ? { ...u, role } : u)) }))
+  },
+
+  banUser: async (userId) => {
+    await repository.banUser(userId)
+    // Re-fetch rather than guessing bannedUntil client-side — the Edge
+    // Function is the one place that actually knows the real value.
+    const users = await repository.listUsers()
+    set({ users })
+  },
+
+  unbanUser: async (userId) => {
+    await repository.unbanUser(userId)
+    const users = await repository.listUsers()
+    set({ users })
+  },
+
+  deleteUser: async (userId) => {
+    await repository.deleteUser(userId)
+    set((state) => ({ users: state.users.filter((u) => u.id !== userId) }))
+  },
+}))
diff --git a/src/state/authStore.ts b/src/state/authStore.ts
index 265e8dc..0eab635 100644
--- a/src/state/authStore.ts
+++ b/src/state/authStore.ts
@@ -1,7 +1,8 @@
 import { create } from 'zustand'
+import type { UserRole } from '../data/AdminUserRepository'
 import { supabase } from '../data/supabaseClient'
 
-export type UserRole = 'regular' | 'admin' | 'super_admin'
+export type { UserRole }
 
 interface AuthStoreState {
   userId: string | null
@@ -10,9 +11,10 @@ interface AuthStoreState {
   isLoaded: boolean
 
   /** One-time fetch of your own profile — nothing else in the app changes
-   *  your own username or role while you're signed in (role changes are an
-   *  Admin/Super-Admin-only action on someone else's account, see
-   *  organized-ideas.md §6, not yet built), so there's no need to keep this live. */
+   *  your own username while you're signed in, and your own role changing
+   *  (a Super-Admin-only action on someone else's account, see
+   *  organized-ideas.md §6) isn't something you'd do to yourself, so
+   *  there's no need to keep this live. */
   load: () => Promise<void>
 }
 
diff --git a/src/state/catalogStore.ts b/src/state/catalogStore.ts
index c59b7ec..6d188e2 100644
--- a/src/state/catalogStore.ts
+++ b/src/state/catalogStore.ts
@@ -3,6 +3,7 @@ import type { CableType, Catalog, DeviceTemplate, PortType } from '../domain/typ
 import type { CatalogRepository } from '../data/CatalogRepository'
 import { cableTypeToRow, deviceTemplateToRow, portTypeToRow } from '../data/catalogRowMapping'
 import { SupabaseCatalogRepository } from '../data/SupabaseCatalogRepository'
+import type { CatalogEntityType } from '../data/SubmissionRepository'
 import { useSubmissionStore } from './submissionStore'
 
 const repository: CatalogRepository = new SupabaseCatalogRepository()
@@ -51,6 +52,16 @@ interface CatalogStoreState {
 
   hidePublicDeviceTemplate: (id: string) => void
   restorePublicDeviceTemplate: (id: string) => void
+
+  /** Admin/Super-Admin direct edit of an already-public entry, per
+   *  organized-ideas.md §6 — bypasses the submission/review workflow
+   *  entirely (RLS's is_admin() clause is what actually permits it). */
+  adminUpdatePortType: (id: string, patch: Partial<Omit<PortType, 'id' | 'custom'>>) => Promise<void>
+  adminUpdateCableType: (id: string, patch: Partial<Omit<CableType, 'id' | 'custom'>>) => Promise<void>
+  adminUpdateDeviceTemplate: (id: string, patch: Partial<Omit<DeviceTemplate, 'id' | 'custom'>>) => Promise<void>
+  /** Unpublishes (is_public -> false) rather than deletes — see
+   *  CatalogRepository.adminUnpublish. */
+  adminUnpublish: (entityType: CatalogEntityType, id: string) => Promise<void>
 }
 
 export const useCatalogStore = create<CatalogStoreState>((set, get) => ({
@@ -140,4 +151,31 @@ export const useCatalogStore = create<CatalogStoreState>((set, get) => ({
     saveHiddenPublicIds(next)
     set({ hiddenPublicDeviceTemplateIds: next })
   },
+
+  // Re-fetch the whole catalog after each of these rather than patching
+  // locally — device_template edits also touch device_template_ports, and
+  // unpublish changes which rows even show up (custom flips true for the
+  // Admin who did it, since is_admin() is the only thing still granting
+  // them visibility — see adminUnpublish's own comment). Simplest correct
+  // thing, and Admin actions here are infrequent enough that the extra
+  // round trip doesn't matter.
+  adminUpdatePortType: async (id, patch) => {
+    await repository.adminUpdatePortType(id, patch)
+    await get().loadCatalog()
+  },
+
+  adminUpdateCableType: async (id, patch) => {
+    await repository.adminUpdateCableType(id, patch)
+    await get().loadCatalog()
+  },
+
+  adminUpdateDeviceTemplate: async (id, patch) => {
+    await repository.adminUpdateDeviceTemplate(id, patch)
+    await get().loadCatalog()
+  },
+
+  adminUnpublish: async (entityType, id) => {
+    await repository.adminUnpublish(entityType, id)
+    await get().loadCatalog()
+  },
 }))
diff --git a/supabase/config.toml b/supabase/config.toml
index 0b60f33..1976a6c 100644
--- a/supabase/config.toml
+++ b/supabase/config.toml
@@ -431,3 +431,18 @@ enabled = true
 # declarative_schema_path = "./schemas"
 # JSON string passed through to pg-delta SQL formatting.
 # format_options = "{\"keywordCase\":\"upper\",\"indent\":2,\"maxWidth\":80,\"commaStyle\":\"trailing\"}"
+
+[functions.admin-user-action]
+enabled = true
+# This function expects a real signed-in user's JWT (auth: 'user' mode in
+# index.ts already verifies it via project JWKS) — verify_jwt = true adds a
+# cheap gateway-level rejection of missing/malformed tokens before the
+# function even runs, on top of that.
+verify_jwt = true
+import_map = "./functions/admin-user-action/deno.json"
+# Uncomment to specify a custom file path to the entrypoint.
+# Supported file extensions are: .ts, .js, .mjs, .jsx, .tsx
+entrypoint = "./functions/admin-user-action/index.ts"
+# Specifies static files to be bundled with the function. Supports glob patterns.
+# For example, if you want to serve static HTML pages in your function:
+# static_files = [ "./functions/admin-user-action/*.html" ]
diff --git a/supabase/functions/admin-user-action/.npmrc b/supabase/functions/admin-user-action/.npmrc
new file mode 100644
index 0000000..48c6388
--- /dev/null
+++ b/supabase/functions/admin-user-action/.npmrc
@@ -0,0 +1,3 @@
+# Configuration for private npm package dependencies
+# For more information on using private registries with Edge Functions, see:
+# https://supabase.com/docs/guides/functions/import-maps#importing-from-private-registries
diff --git a/supabase/functions/admin-user-action/deno.json b/supabase/functions/admin-user-action/deno.json
new file mode 100644
index 0000000..db206e8
--- /dev/null
+++ b/supabase/functions/admin-user-action/deno.json
@@ -0,0 +1,6 @@
+{
+  "imports": {
+    "@supabase/functions-js": "jsr:@supabase/functions-js@^2",
+    "@supabase/server": "npm:@supabase/server@^1"
+  }
+}
diff --git a/supabase/functions/admin-user-action/index.ts b/supabase/functions/admin-user-action/index.ts
new file mode 100644
index 0000000..54bf242
--- /dev/null
+++ b/supabase/functions/admin-user-action/index.ts
@@ -0,0 +1,89 @@
+// Ban/unban/delete a user account — organized-ideas.md §6, Super-Admin only.
+//
+// This has to be an Edge Function rather than a Postgres function (unlike
+// list_users_for_admin or the other privileged functions in this codebase):
+// touching auth.users needs Supabase Auth's Admin API (the stable,
+// documented interface for account mutations), not a direct SQL write to
+// a schema Supabase manages internally and doesn't guarantee stable
+// across upgrades. Ban is reversible (banned_until, no data touched);
+// delete cascades to profiles/diagrams via their existing FKs.
+//
+// To invoke locally (after `supabase start`), with a real user's access
+// token in place of ACCESS_TOKEN:
+//   curl -i --location --request POST 'http://127.0.0.1:54321/functions/v1/admin-user-action' \
+//     --header 'apiKey: <anon key from `supabase status`>' \
+//     --header 'Authorization: Bearer ACCESS_TOKEN' \
+//     --header 'Content-Type: application/json' \
+//     --data '{"action":"ban","userId":"..."}'
+
+import "@supabase/functions-js/edge-runtime.d.ts";
+import { withSupabase } from "@supabase/server";
+
+type Action = "ban" | "unban" | "delete";
+
+interface RequestBody {
+  action: Action;
+  userId: string;
+}
+
+const VALID_ACTIONS: Action[] = ["ban", "unban", "delete"];
+
+// ~100 years — Supabase Auth's own documented idiom for "indefinite ban"
+// (there's no literal "forever" value); "none" is the matching unban value.
+const PERMANENT_BAN_DURATION = "876000h";
+
+export default {
+  fetch: withSupabase({ auth: "user" }, async (req, ctx) => {
+    const callerId = ctx.userClaims!.id;
+
+    // Confirm the caller is a Super Admin by reading their own profile
+    // through the user-scoped (RLS-respecting) client — this leans on the
+    // same "read your own row" policy every other profile read in the app
+    // uses, rather than trusting anything in the JWT itself (its `role`
+    // claim is just "authenticated", not this app's role column).
+    const { data: callerProfile, error: profileError } = await ctx.supabase
+      .from("profiles")
+      .select("role")
+      .eq("id", callerId)
+      .single();
+
+    if (profileError || callerProfile?.role !== "super_admin") {
+      return Response.json({ error: "Only a Super Admin can manage user accounts." }, { status: 403 });
+    }
+
+    let body: RequestBody;
+    try {
+      body = await req.json();
+    } catch {
+      return Response.json({ error: "Invalid request body." }, { status: 400 });
+    }
+
+    const { action, userId } = body;
+    if (typeof userId !== "string" || !userId || !VALID_ACTIONS.includes(action)) {
+      return Response.json({ error: "Request must include a valid action and userId." }, { status: 400 });
+    }
+
+    if (userId === callerId) {
+      return Response.json({ error: "You cannot perform this action on your own account." }, { status: 400 });
+    }
+
+    if (action === "ban") {
+      const { error } = await ctx.supabaseAdmin.auth.admin.updateUserById(userId, {
+        ban_duration: PERMANENT_BAN_DURATION,
+      });
+      if (error) return Response.json({ error: error.message }, { status: 500 });
+    } else if (action === "unban") {
+      const { error } = await ctx.supabaseAdmin.auth.admin.updateUserById(userId, { ban_duration: "none" });
+      if (error) return Response.json({ error: error.message }, { status: 500 });
+    } else {
+      // Cascades to profiles (and from there, diagrams/owned catalog
+      // entries) via their existing `on delete cascade` foreign keys —
+      // the frontend confirmation for this action says so explicitly,
+      // since it's the one irreversible option here.
+      const { error } = await ctx.supabaseAdmin.auth.admin.deleteUser(userId);
+      if (error) return Response.json({ error: error.message }, { status: 500 });
+    }
+
+    return Response.json({ success: true });
+  }),
+};
diff --git a/supabase/migrations/20260912000000_admin_user_management.sql b/supabase/migrations/20260912000000_admin_user_management.sql
new file mode 100644
index 0000000..cc6978b
--- /dev/null
+++ b/supabase/migrations/20260912000000_admin_user_management.sql
@@ -0,0 +1,30 @@
+-- Super-Admin user management (organized-ideas.md §6): "CRUD user accounts"
+-- starts with being able to see them at all. auth.users isn't exposed
+-- through PostgREST (by design — Supabase doesn't expose the `auth` schema
+-- to the API), so this read-only, Super-Admin-gated function is the only
+-- way the app can list users alongside their profile/ban status. The
+-- mutations themselves (ban/unban/delete) go through a new Edge Function
+-- instead of a SQL function here — those specifically need Supabase Auth's
+-- Admin API (auth.admin.updateUserById/deleteUser), the stable, documented
+-- interface for touching auth.users, rather than writing to that schema's
+-- tables directly (undocumented, not guaranteed stable across upgrades).
+
+create or replace function public.list_users_for_admin()
+returns table(id uuid, username text, email text, role text, banned_until timestamptz, created_at timestamptz)
+language plpgsql
+stable
+security definer
+set search_path = public
+as $$
+begin
+  if not public.is_super_admin() then
+    raise exception 'insufficient_privilege' using errcode = '42501';
+  end if;
+
+  return query
+    select p.id, p.username, u.email::text, p.role, u.banned_until, p.created_at
+    from public.profiles p
+    join auth.users u on u.id = p.id
+    order by p.created_at desc;
+end;
+$$;
diff --git a/supabase/tests/rls.sql b/supabase/tests/rls.sql
index e477606..25c80c7 100644
--- a/supabase/tests/rls.sql
+++ b/supabase/tests/rls.sql
@@ -25,7 +25,7 @@ begin;
 
 create extension if not exists pgtap with schema extensions;
 
-select plan(38);
+select plan(43);
 
 -- ----------------------------------------------------------------------
 -- Fixtures (as postgres — RLS does not apply)
@@ -386,6 +386,47 @@ select is(
   'carol (admin) can look up the submitter''s username for a submission she can review'
 );
 
+-- ----------------------------------------------------------------------
+-- Admin user listing (organized-ideas.md §6: "CRUD user accounts" is
+-- Super-Admin-only — even a regular Admin gets 42501 here, unlike the
+-- Admin-gated functions above).
+-- ----------------------------------------------------------------------
+
+select set_config('request.jwt.claim.sub', '22222222-2222-2222-2222-222222222222', true);
+
+select throws_ok(
+  $$ select * from public.list_users_for_admin() $$,
+  '42501'::char(5), null,
+  'bob (regular user) cannot list users'
+);
+
+select set_config('request.jwt.claim.sub', '33333333-3333-3333-3333-333333333333', true);
+
+select throws_ok(
+  $$ select * from public.list_users_for_admin() $$,
+  '42501'::char(5), null,
+  'carol (admin, not super admin) cannot list users'
+);
+
+select set_config('request.jwt.claim.sub', '44444444-4444-4444-4444-444444444444', true);
+
+select lives_ok(
+  $$ select * from public.list_users_for_admin() $$,
+  'dave (super admin) can list users'
+);
+
+select is(
+  (select role from public.list_users_for_admin() where username = 'alice'),
+  'admin',
+  'the listing reflects alice''s current role (promoted earlier in this test run)'
+);
+
+select is(
+  (select email from public.list_users_for_admin() where username = 'alice'),
+  'alice@example.com',
+  'the listing includes email, only readable via this Super-Admin-gated function (not directly through PostgREST)'
+);
+
 select * from finish();
 
 rollback;