diff --git a/Facepunch.Steamworks.Test/AppTest.cs b/Facepunch.Steamworks.Test/AppTest.cs
index d765728..447a1e5 100644
--- a/Facepunch.Steamworks.Test/AppTest.cs
+++ b/Facepunch.Steamworks.Test/AppTest.cs
@@ -14,6 +14,13 @@ namespace Steamworks
 		[AssemblyInitialize]
 		public static void AssemblyInit( TestContext context )
 		{
+			Steamworks.SteamClient.OnCallbackException = ( e ) =>
+			{
+				Console.Error.WriteLine( e.Message );
+				Console.Error.WriteLine( e.StackTrace );
+				Assert.Fail( e.Message );
+			};
+
 			//
 			// Init Client
 			//
diff --git a/Facepunch.Steamworks/SteamClient.cs b/Facepunch.Steamworks/SteamClient.cs
index 206435f..4ccd798 100644
--- a/Facepunch.Steamworks/SteamClient.cs
+++ b/Facepunch.Steamworks/SteamClient.cs
@@ -48,6 +48,8 @@ namespace Steamworks
 			RunCallbacksAsync();
 		}
 
+		public static Action<Exception> OnCallbackException;
+
 		public static bool IsValid => initialized;
 
 		internal static async void RunCallbacksAsync()
@@ -55,14 +57,7 @@ namespace Steamworks
 			while ( IsValid )
 			{
 				await Task.Delay( 16 );
-				try
-				{
-					SteamAPI.RunCallbacks();
-				}
-				catch ( System.Exception )
-				{
-					// TODO - error outputs
-				}
+				RunCallbacks();
 			}
 		}
 
@@ -98,7 +93,14 @@ namespace Steamworks
 
 		public static void RunCallbacks()
 		{
-			SteamAPI.RunCallbacks();
+			try
+			{
+				SteamAPI.RunCallbacks();
+			}
+			catch ( System.Exception e )
+			{
+				OnCallbackException?.Invoke( e );
+			}
 		}
 
 		internal static void UnregisterCallback( IntPtr intPtr )