diff --git a/OpenRA.FileFormats/Session.cs b/OpenRA.FileFormats/Session.cs
index 180848eb97..a661477e0e 100644
--- a/OpenRA.FileFormats/Session.cs
+++ b/OpenRA.FileFormats/Session.cs
@@ -52,6 +52,7 @@ namespace OpenRA.FileFormats
 			public string[] Packages = {};	// filename:sha1 pairs.
 			public string[] Mods = { "ra" };	// mod names
 			public int OrderLatency = 3;
+			public int RandomSeed = 0;
 		}
 	}
 
diff --git a/OpenRA.Game/Game.cs b/OpenRA.Game/Game.cs
index 3f4f86588b..1a91310ffa 100644
--- a/OpenRA.Game/Game.cs
+++ b/OpenRA.Game/Game.cs
@@ -234,6 +234,9 @@ namespace OpenRA
 
 			LobbyInfo = session;
 
+			if (!IsStarted)
+				world.SharedRandom = new OpenRA.Thirdparty.Random(LobbyInfo.GlobalSettings.RandomSeed);
+
 			if (Game.orderManager.Connection.ConnectionState == ConnectionState.Connected)
 				world.SetLocalPlayer(Game.orderManager.Connection.LocalClientId);
 
diff --git a/OpenRA.Game/Server/Server.cs b/OpenRA.Game/Server/Server.cs
index c9879ff5b9..81e76518d7 100644
--- a/OpenRA.Game/Server/Server.cs
+++ b/OpenRA.Game/Server/Server.cs
@@ -43,6 +43,7 @@ namespace OpenRA.Server
 		static string Name;
 		static WebClient wc = new WebClient();
 		static int ExternalPort;
+		static int randomSeed;
 
 		const int DownloadChunkInterval = 20000;
 		const int DownloadChunkSize = 16384;
@@ -61,9 +62,11 @@ namespace OpenRA.Server
 			initialMods = mods;
 			Name = name;
 			ExternalPort = extport;
+			randomSeed = (int)DateTime.Now.ToBinary();
 
 			lobbyInfo = new Session();
 			lobbyInfo.GlobalSettings.Mods = mods;
+			lobbyInfo.GlobalSettings.RandomSeed = randomSeed;
 
 			Console.WriteLine("Initial mods: ");
 			foreach( var m in lobbyInfo.GlobalSettings.Mods )
@@ -548,6 +551,7 @@ namespace OpenRA.Server
 			inFlightFrames.Clear();
 			lobbyInfo = new Session();
 			lobbyInfo.GlobalSettings.Mods = initialMods;
+			lobbyInfo.GlobalSettings.RandomSeed = randomSeed;
 			GameStarted = false;
 		}