diff --git a/SteamKit2/SteamKit2/Steam3/SteamClient/CallbackMgr/CallbackMgr.cs b/SteamKit2/SteamKit2/Steam3/SteamClient/CallbackMgr/CallbackMgr.cs
index 28a8bdee..98342a22 100644
--- a/SteamKit2/SteamKit2/Steam3/SteamClient/CallbackMgr/CallbackMgr.cs
+++ b/SteamKit2/SteamKit2/Steam3/SteamClient/CallbackMgr/CallbackMgr.cs
@@ -75,16 +75,23 @@ namespace SteamKit2
 
             Handle( call );
         }
-        public void RunWaitCallbacks()
+        public void RunWaitCallbacks( TimeSpan timeout )
         {
 #if STATIC_CALLBACKS
-            var call = SteamClient.WaitForCallback( true );
+            var call = SteamClient.WaitForCallback( true, timeout );
 #else
-            var call = client.WaitForCallback( true );
+            var call = client.WaitForCallback( true, timeout );
 #endif
 
+            if ( call == null )
+                return;
+
             Handle( call );
         }
+        public void RunWaitCallbacks()
+        {
+            RunWaitCallbacks( TimeSpan.FromMilliseconds( -1 ) );
+        }
 
 
         internal void Register( ICallback call )