diff --git a/modules/client/rooms/forget.cc b/modules/client/rooms/forget.cc
index 0fa6ddf31..1dfcc0b8c 100644
--- a/modules/client/rooms/forget.cc
+++ b/modules/client/rooms/forget.cc
@@ -17,6 +17,77 @@ post__forget(client &client,
              const resource::request &request,
              const m::room::id &room_id)
 {
+	const m::room room
+	{
+		room_id
+	};
+
+	const m::user::room user_room
+	{
+		request.user_id
+	};
+
+	const auto event_idx
+	{
+		user_room.get(std::nothrow, "ircd.member", room_id)
+	};
+
+	if(!event_idx)
+		throw m::NOT_FOUND
+		{
+			"No user membership found for room %s.",
+			string_view{room_id}
+		};
+
+	char room_membuf[32];
+	const string_view &room_membership
+	{
+		room.membership(room_membuf, request.user_id)
+	};
+
+	char user_membuf[32];
+	string_view user_membership;
+	m::get(std::nothrow, event_idx, "content", [&user_membuf, &user_membership]
+	(const json::object &content)
+	{
+		const json::string &membership
+		{
+			content.get("membership")
+		};
+
+		user_membership =
+		{
+			user_membuf, copy(user_membuf, membership)
+		};
+	});
+
+	if(room_membership != user_membership)
+		log::critical
+		{
+			"Membership mismatch for user %s in room %s: user:%s vs. room:%s",
+			string_view{request.user_id},
+			string_view{room_id},
+			user_membership,
+			room_membership
+		};
+
+	if(user_membership != "leave")
+		throw m::error
+		{
+			http::OK, "M_MEMBERSHIP_NOT_LEAVE",
+			"You must leave the room first to forget it"
+		};
+
+	const auto event_id
+	{
+		m::event_id(event_idx)
+	};
+
+	const auto redact_id
+	{
+		redact(user_room, request.user_id, event_id, "forget")
+	};
+
 	return resource::response
 	{
 		client, http::OK