# Edit Room Membership API This API allows an administrator to join an user account with a given `user_id` to a room with a given `room_id_or_alias`. You can only modify the membership of local users. The server administrator must be in the room and have permission to invite users. ## Parameters The following parameters are available: * `user_id` - Fully qualified user: for example, `@user:server.com`. * `room_id_or_alias` - The room identifier or alias to join: for example, `!636q39766251:server.com`. ## Usage ``` POST /_synapse/admin/v1/join/<room_id_or_alias> { "user_id": "@user:server.com" } ``` Including an `access_token` of a server admin. Response: ``` { "room_id": "!636q39766251:server.com" } ```