diff --git a/public/iserver.h b/public/iserver.h
index eaa9c024..da9f3bad 100644
--- a/public/iserver.h
+++ b/public/iserver.h
@@ -93,6 +93,7 @@ public:
 	virtual ~INetworkServerService() {}
 	virtual INetworkGameServer	*GetIGameServer( void ) = 0;
 	virtual bool	IsActiveInGame( void ) const = 0;
+	virtual bool	unk001( void ) const = 0;
 	virtual bool	IsMultiplayer( void ) const = 0;
 	virtual void	StartupServer( const GameSessionConfiguration_t &config, ISource2WorldSession *pWorldSession, const char * ) = 0;
 	virtual void	SetGameSpawnGroupMgr( IGameSpawnGroupMgr *pMgr ) = 0;