diff --git a/generic.proto b/generic.proto
index 93ad063..287fea9 100644
--- a/generic.proto
+++ b/generic.proto
@@ -17,6 +17,7 @@ message Error {
         OutOfRange = 8;
         NotYourTurn = 9;
         RoomNotAvailable = 10;
+        RoomFull = 11;
     }
     Code code = 2;
 }
@@ -32,13 +33,15 @@ message Operation {
         OK = 2;
         SimpleAuth = 3;
         _MinAuth = 4;
-        SettingsSync = 5;
+        RoomInfoSync = 5;
         PlayfieldSync = 6;
         RobotUpdate = 7;
         YourTurn = 8;
         MakeRoom = 9;
         JoinRoom = 10;
         JoinRandomRoom = 11;
+        LeaveRoom = 12;
+        UserInfoSync = 13;
     }
     Code code = 1;
 }
@@ -58,11 +61,17 @@ message Settings {
     optional uint32 protectCooldown = 5;
     optional uint32 healCooldown = 6;
     optional uint32 healPerTurn = 7;
+    optional uint32 maxPlayers = 8;
 }
 
 
+message UserReference {
+    uint64 clientId = 2;
+    uint64 userId = 3;
+}
 message PublicUserInfo {
     string name = 1;
+    UserReference reference = 2;
 }
 message UserInfo {
     PublicUserInfo publicInfo = 1;
diff --git a/generic.txt b/generic.txt
new file mode 100644
index 0000000..b834d06
--- /dev/null
+++ b/generic.txt
@@ -0,0 +1,27 @@
+Server
+
+void Disconnect() // client closes connection
+void Error(Error)
+void OK()
+SimpleAuth(SimpleAuth) -> UserInfoSync // client wants to authenticate anonymously
+RobotUpdate(Robot) -> RobotUpdate // client wants to change robot
+void RoomInfoSync(RoomInfo) <- TODO // client wants to change room info
+MakeRoom() -> RoomInfoSync // client creates a room
+JoinRoom(???) -> RoomInfoSync // client joins specific room
+JoinRandomRoom() -> RoomInfoSync // client joins random room
+LeaveRoom() -> LeaveRoom // client leaves current room
+
+
+Client
+
+Disconnect() // server closes connection
+Error(Error)
+OK()
+RobotUpdate(Robot) // this robot has changed
+RoomInfoSync(RoomInfo) // your current rooms info has changed
+UserInfoSync(UserInfo) // your user info has been changed
+PlayfielSync(PlayfieldSync) // playfield has been created
+RoomInfoSync(RoomInfo) // room info has changed
+YourTurn() -> RobotUpdate // it's your turn
+JoinRoom(PublicUserInfo) // player joins your current room
+LeaveRoom(UserReference) // player leaves your current room
diff --git a/server/Connection.cpp b/server/Connection.cpp
index 0b32e55..a1b3e5c 100644
--- a/server/Connection.cpp
+++ b/server/Connection.cpp
@@ -1,4 +1,5 @@
 #include "Connection.hpp"
+#include "World.hpp"
 
 #include <optional>
 #include <algorithm>
@@ -19,6 +20,12 @@ asio::awaitable<Packet> Client::receivePacket() {
     case Generic::Operation::SimpleAuth: {
         packet.data = std::make_unique<Generic::SimpleAuth>(co_await receiveProtobuf<Generic::SimpleAuth>(30));
     } break;
+    case Generic::Operation::RobotUpdate: {
+        packet.data = std::make_unique<Generic::Robot>(co_await receiveProtobuf<Generic::Robot>());
+    } break;
+    case Generic::Operation::UserInfoSync:
+    case Generic::Operation::MakeRoom:
+    case Generic::Operation::JoinRandomRoom:
     case Generic::Operation::Disconnect:
     case Generic::Operation::OK:
         break;
@@ -65,14 +72,45 @@ asio::awaitable<void> Client::handlePacket(const Packet& packet) {
         //TODO...
         // Set username
         userInfo.mutable_publicinfo()->set_name(std::move(authData.username()));
+        // Set temporary user and client id
+        auto userRef = userInfo.mutable_publicinfo()->mutable_reference();
+        userRef->set_userid(global.getTemporaryId());
+        userRef->set_clientid(global.getTemporaryId());
         // Mark as authed
         authed = true;
-        // Send OK
-        co_await sendOK();
+        // Send user info
+        Packet userInfoSync;
+        userInfoSync.op.set_code(Generic::Operation::UserInfoSync);
+        userInfoSync.data = std::make_unique<Generic::UserInfo>(userInfo);
+    } break;
+    case Generic::Operation::MakeRoom: {
+        // Create room
+        auto room = std::make_shared<World::Room>(global);
+        global.rooms.push_back(room);
+        co_await room->addClient(shared_from_this());
+    } break;
+    case Generic::Operation::JoinRandomRoom: {
+        // Get random room
+        auto room = global.getRandomRoom();
+        // Check that room was found
+        if (!room) {
+            throw Error("No available room could be found", Generic::Error::RoomNotAvailable);
+        }
+        // Add client to it
+        co_await room->addClient(shared_from_this());
+    } break;
+    case Generic::Operation::LeaveRoom: {
+        // Check that client is in any room
+        if (!currentRoom) {
+            throw Error("You are not in any room", Generic::Error::IllegalOperation);
+        }
+        // Remove client from room
+        co_await currentRoom->removeClient(shared_from_this());
     } break;
     default: {}
     }
-    co_return;
+    // Send OK
+    co_await sendOK();
 }
 
 asio::awaitable<void> Client::connect() {
@@ -111,6 +149,16 @@ asio::awaitable<void> Client::connect() {
     socket.close(ec);
 }
 
+std::shared_ptr<World::Room> Global::getRandomRoom() const {
+    //TODO: Real rng
+    for (const auto& room : rooms) {
+        if (room->isOpen()) {
+            return room;
+        }
+    }
+    return nullptr;
+}
+
 asio::awaitable<void> Server::listen(int port) {
     try {
         // Create acceptor
diff --git a/server/Connection.hpp b/server/Connection.hpp
index 3aadb92..bf358e3 100644
--- a/server/Connection.hpp
+++ b/server/Connection.hpp
@@ -56,6 +56,8 @@ class Client : public std::enable_shared_from_this<Client> {
     bool good = true;
 
 public:
+    World::Room *currentRoom = nullptr;
+
     Client(asio::io_context& ioc, Global& global) : socket(ioc), global(global) {}
 
     asio::awaitable<Packet> receivePacket();
@@ -109,6 +111,13 @@ public:
 struct Global {
     std::vector<std::shared_ptr<Client>> clients;
     std::vector<std::shared_ptr<World::Room>> rooms;
+    uint64_t highestTemporaryId = 0;
+
+    std::shared_ptr<World::Room> getRandomRoom() const;
+
+    uint64_t getTemporaryId() {
+        return ++highestTemporaryId;
+    }
 };
 
 
diff --git a/server/World.cpp b/server/World.cpp
index 5550144..ecccabc 100644
--- a/server/World.cpp
+++ b/server/World.cpp
@@ -29,6 +29,9 @@ void fillSettings(Generic::Settings& settings) {
     if (!settings.has_healperturn()) {
         settings.set_healperturn(2);
     }
+    if (!settings.has_maxplayers()) {
+        settings.set_maxplayers(4);
+    }
 }
 
 boost::asio::awaitable<void> Playfield::reset() {
@@ -138,4 +141,56 @@ Generic::RoomInfo Room::getFullRoomInfo() const {
     }
     return fres;
 }
+
+boost::asio::awaitable<void> Room::addClient(const std::shared_ptr<Connection::Client>& client) {
+    // Check that room is not full
+    if (isFull()) {
+        throw Connection::Error("Room is full", Generic::Error::RoomFull);
+    }
+    // Check that room has no game running
+    if (isRunning()) {
+        throw Connection::Error("Room is in game", Generic::Error::RoomNotAvailable);
+    }
+    // Broadcast join
+    Connection::Packet packet;
+    packet.op.set_code(Generic::Operation::JoinRoom);
+    packet.data = std::make_unique<Generic::PublicUserInfo>(client->getUserInfo().publicinfo());
+    for (auto& client : clients) {
+        co_await client->sendPacket(packet);
+    }
+    // Add client
+    clients.push_back(client);
+    client->currentRoom = this;
+    // Send room info to client
+    packet.op.set_code(Generic::Operation::RoomInfoSync);
+    packet.data = std::make_unique<Generic::RoomInfo>(getFullRoomInfo());
+    co_await client->sendPacket(packet);
+}
+
+boost::asio::awaitable<void> Room::removeClient(const std::shared_ptr<Connection::Client>& client) {
+    // Broadcast leave
+    Connection::Packet packet;
+    packet.op.set_code(Generic::Operation::LeaveRoom);
+    packet.data = std::make_unique<Generic::UserReference>(client->getUserInfo().publicinfo().reference());
+    for (auto& client : clients) {
+        co_await client->sendPacket(packet);
+    }
+    // Remove client from list
+    clients.erase(std::find(clients.begin(), clients.end(), client));
+    client->currentRoom = nullptr;
+    // Remove room if now empty
+    if (clients.empty()) {
+        removeRoom();
+    }
+}
+
+void Room::removeRoom() {
+    global.rooms.erase(std::find_if(global.rooms.begin(), global.rooms.end(), [this] (auto o) {return o.get() == this;}));
+}
+
+boost::asio::awaitable<void> Room::removeAllClients() {
+    for (auto& client : clients) {
+        co_await removeClient(client);
+    }
+}
 }
diff --git a/server/World.hpp b/server/World.hpp
index 4996dc1..91b3824 100644
--- a/server/World.hpp
+++ b/server/World.hpp
@@ -11,6 +11,7 @@
 
 namespace Connection {
 class Client;
+class Global;
 }
 
 namespace World {
@@ -92,15 +93,32 @@ public:
 };
 
 struct Room {
+    Connection::Global &global;
     Generic::RoomInfo info;
     std::vector<std::shared_ptr<Connection::Client>> clients;
     std::unique_ptr<Playfield> playfield = nullptr;
 
+    Room(Connection::Global& global)
+        : global(global) {}
+
     Generic::RoomInfo getFullRoomInfo() const;
+    boost::asio::awaitable<void> addClient(const std::shared_ptr<Connection::Client>& client);
+    boost::asio::awaitable<void> removeClient(const std::shared_ptr<Connection::Client>& client);
+    void removeRoom();
+    boost::asio::awaitable<void> removeAllClients();
 
     bool isMasterClient(const Connection::Client *client) const {
         return client == clients.front().get();
     }
+    bool isFull() const {
+        return clients.size() >= info.settings().maxplayers();
+    }
+    bool isRunning() const {
+        return bool(playfield);
+    }
+    bool isOpen() const {
+        return !isFull() && !isRunning();
+    }
 };
 }
 #endif