diff --git a/client/src/data/rooms.ts b/client/src/data/rooms.ts
index 845b4aa7..494acd25 100644
--- a/client/src/data/rooms.ts
+++ b/client/src/data/rooms.ts
@@ -6,6 +6,7 @@ export type Room = {
   id: string
   ownerId: string
   name: string
+  joinPolicy: string
 }
 
 export type RoomResponse = {
diff --git a/client/src/features/room/organisms/ChatBox.tsx b/client/src/features/room/organisms/ChatBox.tsx
index e5466702..38493869 100644
--- a/client/src/features/room/organisms/ChatBox.tsx
+++ b/client/src/features/room/organisms/ChatBox.tsx
@@ -7,28 +7,40 @@ import { useUserDetails } from '../../../data/users'
 
 export type ChatBoxProps = {
   roomId: string
+  canJoin: boolean
 }
 
-const JoinAlert = ({ roomId }: ChatBoxProps) => {
+const JoinAlert = ({ roomId, canJoin }: ChatBoxProps) => {
   const { mutate: joinRoom, isLoading, isSuccess: isJoined } = useJoinRoom(roomId)
+
   useEffect(() => {
     if (isJoined) {
       window.location.reload()
     }
   }, [isJoined])
+
+  if (canJoin) {
+    return (
+      <Alert status='info' variant='top-accent'>
+        <AlertIcon />
+        You need to join this room to chat.
+        <Spacer />
+        <Button rightIcon={isLoading ? <Spinner /> : undefined} onClick={() => joinRoom()}>
+          Join
+        </Button>
+      </Alert>
+    )
+  }
+
   return (
     <Alert status='info' variant='top-accent'>
       <AlertIcon />
-      You need to join this room to chat.
-      <Spacer />
-      <Button rightIcon={isLoading ? <Spinner /> : undefined} onClick={() => joinRoom()}>
-        Join
-      </Button>
+      You need an invite to join.
     </Alert>
   )
 }
 
-export const ChatBox: React.FC<ChatBoxProps> = ({ roomId }: ChatBoxProps) => {
+export const ChatBox: React.FC<ChatBoxProps> = ({ roomId, canJoin }: ChatBoxProps) => {
   const [content, setContent] = useState<string>('')
   const { data: user, isLoading } = useUserDetails()
   const joined = user?.rooms.some((room) => room.id === roomId)
@@ -54,8 +66,9 @@ export const ChatBox: React.FC<ChatBoxProps> = ({ roomId }: ChatBoxProps) => {
     }
   }
 
+  console.info({ joined })
   if (!isLoading && !joined) {
-    return <JoinAlert roomId={roomId} />
+    return <JoinAlert roomId={roomId} canJoin={canJoin} />
   }
 
   return (
diff --git a/client/src/features/room/pages/Room.tsx b/client/src/features/room/pages/Room.tsx
index f4b24df0..fa4a0f6c 100644
--- a/client/src/features/room/pages/Room.tsx
+++ b/client/src/features/room/pages/Room.tsx
@@ -14,19 +14,20 @@ type Params = {
 
 export const RoomPage = () => {
   const { roomId } = useParams() as Params
-  const { data: roomResponse, isLoading: isLoadingRoom } = useRoom(roomId)
+  const { data: roomResponse } = useRoom(roomId)
 
   const canRead = can('read', roomResponse)
+  const canJoin = can('join', roomResponse)
 
   const { data: messages, isLoading: isLoadingMessages } = useMessages(roomId, { enabled: canRead })
   useMessagesSubscription(roomId, { enabled: canRead })
 
-  if ((canRead && isLoadingMessages) || isLoadingRoom) return <LoadingIndicator />
+  if ((canRead && isLoadingMessages) || !roomResponse) return <LoadingIndicator />
 
   return (
     <Box display='flex' flexFlow='column' height='100%' flex='1'>
       {<MessagesList messages={messages ?? [restrictedMessage(roomId)]} />}
-      <ChatBox roomId={roomId} />
+      <ChatBox roomId={roomId} canJoin={canJoin} />
     </Box>
   )
 }
diff --git a/services/api/src/app/messages/command.service.ts b/services/api/src/app/messages/command.service.ts
index 181a3cff..6f4f7028 100644
--- a/services/api/src/app/messages/command.service.ts
+++ b/services/api/src/app/messages/command.service.ts
@@ -7,6 +7,7 @@ import { RenameUserUseCase } from '@usecases/users/rename';
 import { Dispatcher } from '@entities/messages';
 import { LoremCommandUseCase } from '@usecases/commands/lorem';
 import { ParseCommandUseCase } from '@usecases/commands/parse';
+import { ChangeRoomJoinPolicyUseCase } from '@usecases/rooms/change-room-join-policy';
 
 @Injectable()
 export class CommandService {
@@ -16,6 +17,7 @@ export class CommandService {
     private readonly lorem: LoremCommandUseCase,
     private readonly help: HelpCommandUseCase,
     private readonly parse: ParseCommandUseCase,
+    private readonly changeRoomJoinPolicy: ChangeRoomJoinPolicyUseCase,
     readonly dispatcher: Dispatcher,
   ) {}
 
@@ -35,6 +37,12 @@ export class CommandService {
       case 'lorem':
         await this.lorem.exec({ ...params, roomId, authenticatedUser });
         break;
+      case 'changeRoomJoinPolicy':
+        await this.changeRoomJoinPolicy.exec({
+          ...params,
+          roomId,
+          authenticatedUser,
+        });
     }
   }
 }
diff --git a/services/api/src/app/messages/messages.module.ts b/services/api/src/app/messages/messages.module.ts
index 44140b93..4065e3dd 100644
--- a/services/api/src/app/messages/messages.module.ts
+++ b/services/api/src/app/messages/messages.module.ts
@@ -12,6 +12,7 @@ import { HelpCommandUseCase } from '@usecases/commands/help';
 import { LoremCommandUseCase, LoremGenerator } from '@usecases/commands/lorem';
 import { FakerLoremGenerator } from './faker.lorem.generator';
 import { DispatcherModule } from '../dispatcher/dispatcher.module';
+import { ChangeRoomJoinPolicyUseCase } from '@usecases/rooms/change-room-join-policy';
 
 @Module({
   imports: [AuthModule, DispatcherModule],
@@ -28,6 +29,7 @@ import { DispatcherModule } from '../dispatcher/dispatcher.module';
     CommandService,
     RenameRoomUseCase,
     RenameUserUseCase,
+    ChangeRoomJoinPolicyUseCase,
     LoremCommandUseCase,
     HelpCommandUseCase,
   ],
diff --git a/services/api/src/domain/entities/rooms.repository.ts b/services/api/src/domain/entities/rooms.repository.ts
index a98d535b..07a5cba7 100644
--- a/services/api/src/domain/entities/rooms.repository.ts
+++ b/services/api/src/domain/entities/rooms.repository.ts
@@ -1,7 +1,9 @@
 import { Room } from './room.entity';
 
 export type CreateRoomParams = Omit<Room, 'id'>;
-export type UpdateRoomParams = Partial<Pick<Room, 'name'>> & Pick<Room, 'id'>;
+export type UpdateRoomParams = Partial<
+  Pick<Room, 'name' | 'id' | 'joinPolicy'>
+>;
 
 export abstract class RoomsRepository {
   abstract createRoom(params: CreateRoomParams): Promise<Room>;
diff --git a/services/api/src/domain/usecases/commands/help.spec.ts b/services/api/src/domain/usecases/commands/help.spec.ts
index 59459f53..d0b86796 100644
--- a/services/api/src/domain/usecases/commands/help.spec.ts
+++ b/services/api/src/domain/usecases/commands/help.spec.ts
@@ -32,6 +32,7 @@ describe('HelpCommandUseCase', () => {
         "* `/lorem {count} {'words' | 'paragraphs'}`: generate lorem text",
         '* `/rename room {name}`: change the room name',
         '* `/rename user {name}`: change your display name',
+        "* `/set room join policy {'anyone', 'invite'}`: set the room join policy",
       ].join('\n'),
     });
   });
diff --git a/services/api/src/domain/usecases/commands/parse/command.parser.ts b/services/api/src/domain/usecases/commands/parse/command.parser.ts
index 81255801..f173a496 100644
--- a/services/api/src/domain/usecases/commands/parse/command.parser.ts
+++ b/services/api/src/domain/usecases/commands/parse/command.parser.ts
@@ -1,4 +1,5 @@
 import { Command } from '@entities/command.entity';
+import { JoinPolicy } from '@entities/room.entity';
 import { BadRequestException } from '@nestjs/common';
 import { equals } from 'rambda';
 import { z, ZodIssue, ZodType } from 'zod';
@@ -7,6 +8,7 @@ export type ParsedCommand =
   | { tag: 'help'; params: null }
   | { tag: 'renameRoom'; params: { newName: string } }
   | { tag: 'renameUser'; params: { newName: string } }
+  | { tag: 'changeRoomJoinPolicy'; params: { newJoinPolicy: JoinPolicy } }
   | {
       tag: 'lorem';
       params: { count: number; typeToken: 'words' | 'paragraphs' };
diff --git a/services/api/src/domain/usecases/commands/parse/parsers/change-room-join-policy-parser.ts b/services/api/src/domain/usecases/commands/parse/parsers/change-room-join-policy-parser.ts
new file mode 100644
index 00000000..4b50d455
--- /dev/null
+++ b/services/api/src/domain/usecases/commands/parse/parsers/change-room-join-policy-parser.ts
@@ -0,0 +1,24 @@
+import { z } from 'zod';
+import { CommandParser, ParsedCommand } from '../command.parser';
+import { JoinPolicy } from '@entities/room.entity';
+
+const schema = z
+  .tuple([
+    z.literal('set'),
+    z.literal('room'),
+    z.literal('join'),
+    z.literal('policy'),
+    z.enum([JoinPolicy.Anyone, JoinPolicy.Invite]),
+  ])
+  .rest(z.string())
+  .transform<ParsedCommand>(([, , , , joinPolicy]) => ({
+    tag: 'changeRoomJoinPolicy',
+    params: { newJoinPolicy: joinPolicy },
+  }));
+
+export const changeRoomJoinPolicyParser = new CommandParser({
+  matchTokens: ['set', 'room', 'join', 'policy'],
+  schema,
+  signature: `/set room join policy {'anyone', 'invite'}`,
+  summary: 'set the room join policy',
+});
diff --git a/services/api/src/domain/usecases/commands/parse/parsers/index.ts b/services/api/src/domain/usecases/commands/parse/parsers/index.ts
index a3065910..316ff6d6 100644
--- a/services/api/src/domain/usecases/commands/parse/parsers/index.ts
+++ b/services/api/src/domain/usecases/commands/parse/parsers/index.ts
@@ -1,4 +1,5 @@
 import { CommandParser } from '../command.parser';
+import { changeRoomJoinPolicyParser } from './change-room-join-policy-parser';
 import { helpParser } from './help.parser';
 import { loremParser } from './lorem.parser';
 import { renameRoomParser } from './rename.room.parser';
@@ -9,4 +10,5 @@ export const parsers: CommandParser[] = [
   loremParser,
   renameRoomParser,
   renameUserParser,
+  changeRoomJoinPolicyParser,
 ];
diff --git a/services/api/src/domain/usecases/rooms/change-room-join-policy.spec.ts b/services/api/src/domain/usecases/rooms/change-room-join-policy.spec.ts
new file mode 100644
index 00000000..b6f83224
--- /dev/null
+++ b/services/api/src/domain/usecases/rooms/change-room-join-policy.spec.ts
@@ -0,0 +1,84 @@
+import { TestAuthService } from '@fixtures/auth/test-auth-service';
+import { TestRoomsRepository } from '@fixtures/data/test.rooms.repository';
+import { mock, MockProxy } from 'jest-mock-extended';
+import { RoomFactory } from '@fixtures/messages/room.factory';
+import { UserFactory } from '@fixtures/messages/user.factory';
+import { UnauthorizedException } from '@nestjs/common';
+import { Dispatcher } from '@entities/messages';
+import { AppLogger } from '@app/app.logger';
+import { Role } from '@usecases/auth.service';
+import { ChangeRoomJoinPolicyUseCase } from './change-room-join-policy';
+import { JoinPolicy } from '@entities/room.entity';
+
+describe('ChangeRoomJoinPolicyUseCase', () => {
+  let changeRoomJoinPolicy: ChangeRoomJoinPolicyUseCase;
+  let rooms: TestRoomsRepository;
+  let auth: TestAuthService;
+  let dispatcher: MockProxy<Dispatcher>;
+
+  const originalJoinPolicy = JoinPolicy.Invite;
+  const newJoinPolicy = JoinPolicy.Anyone;
+
+  const owner = UserFactory.build();
+  const otherUser = UserFactory.build();
+  const room = RoomFactory.build({ joinPolicy: originalJoinPolicy });
+
+  beforeEach(() => {
+    rooms = new TestRoomsRepository();
+    rooms.setData([room]);
+
+    auth = new TestAuthService(mock<AppLogger>());
+    auth.stubPermission({ user: owner, subject: room, action: Role.Manage });
+
+    dispatcher = mock<Dispatcher>();
+
+    changeRoomJoinPolicy = new ChangeRoomJoinPolicyUseCase(
+      rooms,
+      auth,
+      dispatcher,
+    );
+  });
+
+  it('renames the room', async () => {
+    await changeRoomJoinPolicy.exec({
+      roomId: room.id,
+      authenticatedUser: owner,
+      newJoinPolicy,
+    });
+
+    const updatedRoom = await rooms.getRoom(room.id);
+    expect(updatedRoom.joinPolicy).toEqual(newJoinPolicy);
+  });
+
+  it('sends a notification', async () => {
+    await changeRoomJoinPolicy.exec({
+      roomId: room.id,
+      authenticatedUser: owner,
+      newJoinPolicy,
+    });
+
+    expect(dispatcher.send).toHaveBeenCalledWith({
+      content: 'Room join policy updated to anyone',
+      authorId: 'system',
+      roomId: room.id,
+      updatedEntities: ['room'],
+    });
+  });
+
+  it('authorizes the user', async () => {
+    await expect(
+      changeRoomJoinPolicy.exec({
+        roomId: room.id,
+        authenticatedUser: otherUser,
+        newJoinPolicy,
+      }),
+    ).rejects.toEqual(
+      new UnauthorizedException(
+        `You cannot change this room's join policy. Only the owner can do this.`,
+      ),
+    );
+
+    const updatedRoom = await rooms.getRoom(room.id);
+    expect(updatedRoom.joinPolicy).toEqual(originalJoinPolicy);
+  });
+});
diff --git a/services/api/src/domain/usecases/rooms/change-room-join-policy.ts b/services/api/src/domain/usecases/rooms/change-room-join-policy.ts
new file mode 100644
index 00000000..9badab4c
--- /dev/null
+++ b/services/api/src/domain/usecases/rooms/change-room-join-policy.ts
@@ -0,0 +1,50 @@
+import { Dispatcher, DraftMessage, UpdatedEntity } from '@entities/messages';
+import { JoinPolicy } from '@entities/room.entity';
+import { RoomsRepository } from '@entities/rooms.repository';
+import { User } from '@entities/users';
+import { Injectable } from '@nestjs/common';
+import { AuthService, Role } from '@usecases/auth.service';
+
+export type ChangeRoomJoinPolicyParams = {
+  roomId: string;
+  authenticatedUser: User;
+  newJoinPolicy: JoinPolicy;
+};
+
+@Injectable()
+export class ChangeRoomJoinPolicyUseCase {
+  constructor(
+    private readonly rooms: RoomsRepository,
+    private readonly authService: AuthService,
+    private readonly dispatcher: Dispatcher,
+  ) {}
+
+  async exec({
+    roomId,
+    authenticatedUser,
+    newJoinPolicy,
+  }: ChangeRoomJoinPolicyParams): Promise<void> {
+    const room = await this.rooms.getRoom(roomId);
+
+    await this.authService.authorize({
+      user: authenticatedUser,
+      subject: room,
+      action: Role.Manage,
+      message: `You cannot change this room's join policy. Only the owner can do this.`,
+    });
+
+    await this.rooms.updateRoom({
+      id: roomId,
+      joinPolicy: newJoinPolicy,
+    });
+
+    const message: DraftMessage = {
+      content: `Room join policy updated to ${newJoinPolicy}`,
+      roomId: room.id,
+      authorId: 'system',
+      updatedEntities: [UpdatedEntity.Room],
+    };
+
+    await this.dispatcher.send(message);
+  }
+}
diff --git a/services/api/src/domain/usecases/rooms/create.spec.ts b/services/api/src/domain/usecases/rooms/create.spec.ts
index d9cb3d3f..61a388b5 100644
--- a/services/api/src/domain/usecases/rooms/create.spec.ts
+++ b/services/api/src/domain/usecases/rooms/create.spec.ts
@@ -2,6 +2,7 @@ import { TestMembershipsRepository } from '@fixtures/data/test.memberships.repos
 import { TestRoomsRepository } from '@fixtures/data/test.rooms.repository';
 import { UserFactory } from '@fixtures/messages/user.factory';
 import { CreateRoomUseCase } from './create';
+import { ContentPolicy, JoinPolicy } from '@entities/room.entity';
 
 describe('CreateRoomUseCase', () => {
   let create: CreateRoomUseCase;
@@ -23,8 +24,8 @@ describe('CreateRoomUseCase', () => {
     const room = await create.exec(owner);
     expect(room).toMatchObject({
       ownerId: owner.id,
-      contentPolicy: 'private',
-      joinPolicy: 'anyone',
+      contentPolicy: ContentPolicy.Private,
+      joinPolicy: JoinPolicy.Invite,
     });
   });
 
diff --git a/services/api/src/domain/usecases/rooms/create.ts b/services/api/src/domain/usecases/rooms/create.ts
index 7eb438e0..65c69f7a 100644
--- a/services/api/src/domain/usecases/rooms/create.ts
+++ b/services/api/src/domain/usecases/rooms/create.ts
@@ -19,7 +19,7 @@ export class CreateRoomUseCase {
       ownerId: owner.id,
       name: titleCase(name),
       contentPolicy: ContentPolicy.Private,
-      joinPolicy: JoinPolicy.Anyone,
+      joinPolicy: JoinPolicy.Invite,
     });
     await this.memberships.createMembership({
       userId: owner.id,