diff --git a/core-legacy/ISmmPlugin.h b/core-legacy/ISmmPlugin.h
index 67315ff..533a7ba 100644
--- a/core-legacy/ISmmPlugin.h
+++ b/core-legacy/ISmmPlugin.h
@@ -25,6 +25,13 @@
 
 class ISmmAPI;
 
+// Interface return status, binary-compatible with HL2SDK's IFACE_OK and IFACE_FAILED.
+enum 
+{
+	META_IFACE_OK = 0,
+	META_IFACE_FAILED
+};
+
 class ISmmPlugin
 {
 public:
diff --git a/core/ISmmPlugin.h b/core/ISmmPlugin.h
index ab750d6..12a0665 100644
--- a/core/ISmmPlugin.h
+++ b/core/ISmmPlugin.h
@@ -39,6 +39,13 @@
 #include <ISmmAPI.h>
 #include <ISmmPluginExt.h>
 
+// Interface return status, binary-compatible with HL2SDK's IFACE_OK and IFACE_FAILED.
+enum 
+{
+	META_IFACE_OK = 0,
+	META_IFACE_FAILED
+};
+
 namespace SourceMM
 {
 	class ISmmAPI;
diff --git a/core/ISmmPluginExt.h b/core/ISmmPluginExt.h
index 7d17c4a..5e24284 100644
--- a/core/ISmmPluginExt.h
+++ b/core/ISmmPluginExt.h
@@ -28,13 +28,6 @@
 
 #include <stddef.h>
 
-// Interface return status, binary-compatible with HL2SDK's IFACE_OK and IFACE_FAILED.
-enum 
-{
-	META_IFACE_OK = 0,
-	META_IFACE_FAILED
-};
-
 /**
  * @file ISmmPluginExt.h Provides an alternate method for loading plugins, 
  * without needing to include the default headers and all their Half-Life baggage.