diff --git a/core/ISmmAPI.h b/core/ISmmAPI.h
index f9c916d..ef5ed9f 100644
--- a/core/ISmmAPI.h
+++ b/core/ISmmAPI.h
@@ -34,6 +34,8 @@
  */
 
 #include <stdarg.h>
+#include <interface.h>
+#include <eiface.h>
 #include <sourcehook.h>
 #include <IPluginManager.h>
 #include <ISmmPlugin.h>
@@ -50,24 +52,6 @@
 #define MMIFACE_SH_HOOKMANAUTOGEN	"IHookManagerAutoGen"		/**< SourceHook::IHookManagerAutoGen Pointer */
 #define IFACE_MAXNUM			999						/**< Maximum interface version */
 
-#if defined META_NO_HL2SDK
-class CGlobalVars;
-class IServerPluginCallbacks;
-struct edict_t;
-class ConCommandBase;
-#else
-#include <eiface.h>
-#endif
-
-// Interface return status, binary-compatible with HL2SDK's IFACE_OK and IFACE_FAILED.
-enum 
-{
-	META_IFACE_OK = 0,
-	META_IFACE_FAILED
-};
-
-typedef void* (*CreateInterfaceFn)(const char *pName, int *pReturnCode);
-
 namespace SourceMM
 {
 	class ISmmPlugin;
diff --git a/core/ISmmPlugin.h b/core/ISmmPlugin.h
index ab750d6..c959556 100644
--- a/core/ISmmPlugin.h
+++ b/core/ISmmPlugin.h
@@ -34,6 +34,7 @@
  * The pure-virtual ISmmPlugin callbacks must be implemented for the load to load.
  */
 
+#include <interface.h>
 #include <sourcehook.h>
 #include <IPluginManager.h>
 #include <ISmmAPI.h>
@@ -267,7 +268,7 @@ namespace SourceMM
 		 * wrapper.  This can be used to provide interfaces to other plugins or
 		 * the GameDLL.
 		 *
-		 * If ret is passed, you should fill it with META_IFACE_OK or META_IFACE_FAILED.
+		 * If ret is passed, you should fill it with IFACE_OK or IFACE_FAILED.
 		 *
 		 * @param iface			Interface string.
 		 * @param ret			Optional pointer to store return code.
@@ -278,7 +279,7 @@ namespace SourceMM
 		{
 			if (ret)
 			{
-				*ret = META_IFACE_FAILED;
+				*ret = IFACE_FAILED;
 			}
 
 			return NULL; 
@@ -289,7 +290,7 @@ namespace SourceMM
 		 * Metamod:Source's wrapper. This can be used to provide interfaces to 
 		 * other plugins.
 		 *
-		 * If ret is passed, you should fill it with META_IFACE_OK or META_IFACE_FAILED.
+		 * If ret is passed, you should fill it with IFACE_OK or IFACE_FAILED.
 		 *
 		 * @param iface			Interface string.
 		 * @param ret			Optional pointer to store return code.
@@ -300,7 +301,7 @@ namespace SourceMM
 		{
 			if (ret)
 			{
-				*ret = META_IFACE_FAILED;
+				*ret = IFACE_FAILED;
 			}
 	
 			return NULL; 
@@ -311,7 +312,7 @@ namespace SourceMM
 		 * Metamod:Source's wrapper.  This can be used to provide interfaces to 
 		 * other plugins.
 		 *
-		 * If ret is passed, you should fill it with META_IFACE_OK or META_IFACE_FAILED.
+		 * If ret is passed, you should fill it with IFACE_OK or IFACE_FAILED.
 		 *
 		 * @param iface			Interface string.
 		 * @param ret			Optional pointer to store return code.
@@ -322,7 +323,7 @@ namespace SourceMM
 		{
 			if (ret)
 			{
-				*ret = META_IFACE_FAILED;
+				*ret = IFACE_FAILED;
 			}
 			
 			return NULL; 
@@ -333,7 +334,7 @@ namespace SourceMM
 		 * Metamod:Source's wrapper.  This can be used to provide interfaces to 
 		 * other plugins.
 		 *
-		 * If ret is passed, you should fill it with META_IFACE_OK or META_IFACE_FAILED.
+		 * If ret is passed, you should fill it with IFACE_OK or IFACE_FAILED.
 		 *
 		 * @param iface			Interface string.
 		 * @param ret			Optional pointer to store return code.
@@ -344,7 +345,7 @@ namespace SourceMM
 		{
 			if (ret)
 			{
-				*ret = META_IFACE_FAILED;
+				*ret = IFACE_FAILED;
 			}
 	
 			return NULL; 
@@ -354,7 +355,7 @@ namespace SourceMM
 		 * @brief Called when Metamod's own factory is invoked.  
 		 * This can be used to provide interfaces to other plugins.
 		 *
-		 * If ret is passed, you should fill it with META_IFACE_OK or META_IFACE_FAILED.
+		 * If ret is passed, you should fill it with IFACE_OK or IFACE_FAILED.
 		 *
 		 * @param iface			Interface string.
 		 * @param ret			Optional pointer to store return code.
@@ -365,7 +366,7 @@ namespace SourceMM
 		{
 			if (ret)
 			{
-				*ret = META_IFACE_FAILED;
+				*ret = IFACE_FAILED;
 			}
 	
 			return NULL;