1 files changed, 16 insertions, 0 deletions
diff --git a/src/mscorlib/shared/System/Threading/ApartmentState.cs b/src/mscorlib/shared/System/Threading/ApartmentState.cs
new file mode 100644
index 0000000000..47c1677cb5
--- /dev/null
+++ b/src/mscorlib/shared/System/Threading/ApartmentState.cs
@@ -0,0 +1,16 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace System.Threading
+{
+    public enum ApartmentState
+    {
+        /*=========================================================================
+        ** Constants for thread apartment states.
+        =========================================================================*/
+        STA = 0,
+        MTA = 1,
+        Unknown = 2
+    }
+}