diff --git a/sp/src/game/server/ai_basenpc.h b/sp/src/game/server/ai_basenpc.h
index 74ef79bf..c37ba2fc 100644
--- a/sp/src/game/server/ai_basenpc.h
+++ b/sp/src/game/server/ai_basenpc.h
@@ -98,6 +98,11 @@ extern bool AIStrongOpt( void );
 #ifdef MAPBASE
 // Defines Mapbase's extended NPC response system usage.
 #define EXPANDED_RESPONSE_SYSTEM_USAGE
+
+// Use the model keyvalue if it is defined
+#define DefaultOrCustomModel(defaultModel) GetModelName() != NULL_STRING ? STRING(GetModelName()) : defaultModel
+#else
+#define DefaultOrCustomModel() defaultModel
 #endif
 
 #ifdef EXPANDED_RESPONSE_SYSTEM_USAGE
diff --git a/sp/src/game/server/hl2/npc_antlion.cpp b/sp/src/game/server/hl2/npc_antlion.cpp
index d94c658d..66fd8367 100644
--- a/sp/src/game/server/hl2/npc_antlion.cpp
+++ b/sp/src/game/server/hl2/npc_antlion.cpp
@@ -277,17 +277,17 @@ void CNPC_Antlion::Spawn( void )
 #ifdef HL2_EPISODIC
 	if ( IsWorker() )
 	{
-		SetModel( ANTLION_WORKER_MODEL );
+		SetModel( DefaultOrCustomModel(ANTLION_WORKER_MODEL) );
 		AddSpawnFlags( SF_NPC_LONG_RANGE );
 		SetBloodColor( BLOOD_COLOR_ANTLION_WORKER );
 	}
 	else
 	{
-		SetModel( ANTLION_MODEL );
+		SetModel( DefaultOrCustomModel(ANTLION_MODEL) );
 		SetBloodColor( BLOOD_COLOR_ANTLION );
 	}
 #else
-	SetModel( ANTLION_MODEL );
+	SetModel( DefaultOrCustomModel(ANTLION_MODEL) );
 	SetBloodColor( BLOOD_COLOR_YELLOW );
 #endif // HL2_EPISODIC
 
diff --git a/sp/src/game/server/hl2/npc_antlionguard.cpp b/sp/src/game/server/hl2/npc_antlionguard.cpp
index efc5883d..57592617 100644
--- a/sp/src/game/server/hl2/npc_antlionguard.cpp
+++ b/sp/src/game/server/hl2/npc_antlionguard.cpp
@@ -678,7 +678,7 @@ void CNPC_AntlionGuard::UpdateOnRemove( void )
 //-----------------------------------------------------------------------------
 void CNPC_AntlionGuard::Precache( void )
 {
-	PrecacheModel( ANTLIONGUARD_MODEL );
+	PrecacheModel( DefaultOrCustomModel( ANTLIONGUARD_MODEL ) );
 
 	PrecacheScriptSound( "NPC_AntlionGuard.Shove" );
 	PrecacheScriptSound( "NPC_AntlionGuard.HitHard" );
@@ -779,7 +779,7 @@ void CNPC_AntlionGuard::Spawn( void )
 {
 	Precache();
 
-	SetModel( ANTLIONGUARD_MODEL );
+	SetModel( DefaultOrCustomModel( ANTLIONGUARD_MODEL ) );
 
 	// Switch our skin (for now), if we're the cavern guard
 	if ( m_bCavernBreed )
diff --git a/sp/src/game/server/hl2/npc_barnacle.cpp b/sp/src/game/server/hl2/npc_barnacle.cpp
index 68b7064c..2ffca3bc 100644
--- a/sp/src/game/server/hl2/npc_barnacle.cpp
+++ b/sp/src/game/server/hl2/npc_barnacle.cpp
@@ -266,7 +266,7 @@ void CNPC_Barnacle::Spawn()
 {
 	Precache( );
 
-	SetModel( "models/barnacle.mdl" );
+	SetModel( DefaultOrCustomModel( "models/barnacle.mdl" ) );
 	UTIL_SetSize( this, Vector(-16, -16, -40), Vector(16, 16, 0) );
 
 	SetSolid( SOLID_BBOX );
@@ -2375,7 +2375,7 @@ const impactdamagetable_t &CNPC_Barnacle::GetPhysicsImpactDamageTable( void )
 //=========================================================
 void CNPC_Barnacle::Precache()
 {
-	PrecacheModel("models/barnacle.mdl");
+	PrecacheModel( DefaultOrCustomModel( "models/barnacle.mdl" ) );
 
 	// Precache all gibs
 	for ( int i=0; i < ARRAYSIZE(m_szGibNames); i++ )
diff --git a/sp/src/game/server/hl2/npc_headcrab.cpp b/sp/src/game/server/hl2/npc_headcrab.cpp
index 22f44d3d..b1b8db81 100644
--- a/sp/src/game/server/hl2/npc_headcrab.cpp
+++ b/sp/src/game/server/hl2/npc_headcrab.cpp
@@ -2433,7 +2433,7 @@ void CBaseHeadcrab::CreateDust( bool placeDecal )
 //-----------------------------------------------------------------------------
 void CHeadcrab::Precache( void )
 {
-	PrecacheModel( "models/headcrabclassic.mdl" );
+	PrecacheModel( DefaultOrCustomModel( "models/headcrabclassic.mdl" ) );
 
 	PrecacheScriptSound( "NPC_HeadCrab.Gib" );
 	PrecacheScriptSound( "NPC_HeadCrab.Idle" );
@@ -2455,7 +2455,7 @@ void CHeadcrab::Precache( void )
 void CHeadcrab::Spawn( void )
 {
 	Precache();
-	SetModel( "models/headcrabclassic.mdl" );
+	SetModel( DefaultOrCustomModel( "models/headcrabclassic.mdl" ) );
 
 	BaseClass::Spawn();
 
@@ -2570,7 +2570,7 @@ END_DATADESC()
 //-----------------------------------------------------------------------------
 void CFastHeadcrab::Precache( void )
 {
-	PrecacheModel( "models/headcrab.mdl" );
+	PrecacheModel( DefaultOrCustomModel( "models/headcrab.mdl" ) );
 
 	PrecacheScriptSound( "NPC_FastHeadcrab.Idle" );
 	PrecacheScriptSound( "NPC_FastHeadcrab.Alert" );
@@ -2589,7 +2589,7 @@ void CFastHeadcrab::Precache( void )
 void CFastHeadcrab::Spawn( void )
 {
 	Precache();
-	SetModel( "models/headcrab.mdl" );
+	SetModel( DefaultOrCustomModel( "models/headcrab.mdl" ) );
 
 	BaseClass::Spawn();
 
@@ -3089,7 +3089,7 @@ void CBlackHeadcrab::TelegraphSound( void )
 void CBlackHeadcrab::Spawn( void )
 {
 	Precache();
-	SetModel( "models/headcrabblack.mdl" );
+	SetModel( DefaultOrCustomModel( "models/headcrabblack.mdl" ) );
 
 	BaseClass::Spawn();
 
@@ -3106,7 +3106,7 @@ void CBlackHeadcrab::Spawn( void )
 //-----------------------------------------------------------------------------
 void CBlackHeadcrab::Precache( void )
 {
-	PrecacheModel( "models/headcrabblack.mdl" );
+	PrecacheModel( DefaultOrCustomModel( "models/headcrabblack.mdl" ) );
 
 	PrecacheScriptSound( "NPC_BlackHeadcrab.Telegraph" );
 	PrecacheScriptSound( "NPC_BlackHeadcrab.Attack" );
diff --git a/sp/src/game/server/hl2/npc_manhack.cpp b/sp/src/game/server/hl2/npc_manhack.cpp
index 27dcde85..e221e938 100644
--- a/sp/src/game/server/hl2/npc_manhack.cpp
+++ b/sp/src/game/server/hl2/npc_manhack.cpp
@@ -2193,9 +2193,9 @@ void CNPC_Manhack::Precache(void)
 	//
 	// Model.
 	//
-	PrecacheModel("models/manhack.mdl");
+	PrecacheModel( DefaultOrCustomModel( "models/manhack.mdl" ) );
 	PrecacheModel( MANHACK_GLOW_SPRITE );
-	PropBreakablePrecacheAll( MAKE_STRING("models/manhack.mdl") );
+	PropBreakablePrecacheAll( MAKE_STRING( DefaultOrCustomModel( "models/manhack.mdl" ) ) );
 	
 	PrecacheScriptSound( "NPC_Manhack.Die" );
 	PrecacheScriptSound( "NPC_Manhack.Bat" );
@@ -2389,7 +2389,7 @@ void CNPC_Manhack::Spawn(void)
 	AddSpawnFlags( SF_NPC_FADE_CORPSE );
 #endif // _XBOX
 
-	SetModel( "models/manhack.mdl" );
+	SetModel( DefaultOrCustomModel( "models/manhack.mdl" ) );
 	SetHullType(HULL_TINY_CENTERED); 
 	SetHullSizeNormal();
 
diff --git a/sp/src/game/server/hl2/npc_scanner.cpp b/sp/src/game/server/hl2/npc_scanner.cpp
index 55716451..aac717c5 100644
--- a/sp/src/game/server/hl2/npc_scanner.cpp
+++ b/sp/src/game/server/hl2/npc_scanner.cpp
@@ -256,11 +256,11 @@ void CNPC_CScanner::Spawn(void)
 
 	if( m_bIsClawScanner )
 	{
-		SetModel( "models/shield_scanner.mdl");
+		SetModel( DefaultOrCustomModel( "models/shield_scanner.mdl" ) );
 	}
 	else
 	{
-		SetModel( "models/combine_scanner.mdl");
+		SetModel( DefaultOrCustomModel( "models/combine_scanner.mdl" ) );
 	}
 
 	m_iHealth				= sk_scanner_health.GetFloat();
@@ -565,7 +565,7 @@ void CNPC_CScanner::Precache(void)
 	// Model
 	if( m_bIsClawScanner )
 	{
-		PrecacheModel("models/shield_scanner.mdl");
+		PrecacheModel( DefaultOrCustomModel( "models/shield_scanner.mdl" ) );
 
 		PrecacheModel("models/gibs/Shield_Scanner_Gib1.mdl");
 		PrecacheModel("models/gibs/Shield_Scanner_Gib2.mdl");
@@ -591,7 +591,7 @@ void CNPC_CScanner::Precache(void)
 	}
 	else
 	{
-		PrecacheModel("models/combine_scanner.mdl");
+		PrecacheModel( DefaultOrCustomModel( "models/combine_scanner.mdl" ) );
 
 		PrecacheModel("models/gibs/scanner_gib01.mdl" );
 		PrecacheModel("models/gibs/scanner_gib02.mdl" );	
diff --git a/sp/src/game/server/hl2/npc_stalker.cpp b/sp/src/game/server/hl2/npc_stalker.cpp
index 0165c29d..67ed567a 100644
--- a/sp/src/game/server/hl2/npc_stalker.cpp
+++ b/sp/src/game/server/hl2/npc_stalker.cpp
@@ -278,7 +278,7 @@ void CNPC_Stalker::Spawn( void )
 {
 	Precache( );
 
-	SetModel( "models/stalker.mdl" );
+	SetModel( DefaultOrCustomModel( "models/stalker.mdl" ) );
 	SetHullType(HULL_HUMAN);
 	SetHullSizeNormal();
 
@@ -321,7 +321,7 @@ void CNPC_Stalker::Spawn( void )
 //-----------------------------------------------------------------------------
 void CNPC_Stalker::Precache( void )
 {
-	PrecacheModel("models/stalker.mdl");
+	PrecacheModel( DefaultOrCustomModel( "models/stalker.mdl" ) );
 	PrecacheModel("sprites/laser.vmt");	
 
 	PrecacheModel("sprites/redglow1.vmt");
diff --git a/sp/src/game/server/hl2/npc_turret_ceiling.cpp b/sp/src/game/server/hl2/npc_turret_ceiling.cpp
index bc4f6821..0637525a 100644
--- a/sp/src/game/server/hl2/npc_turret_ceiling.cpp
+++ b/sp/src/game/server/hl2/npc_turret_ceiling.cpp
@@ -304,7 +304,7 @@ CNPC_CeilingTurret::~CNPC_CeilingTurret( void )
 //-----------------------------------------------------------------------------
 void CNPC_CeilingTurret::Precache( void )
 {
-	PrecacheModel( CEILING_TURRET_MODEL );	
+	PrecacheModel( DefaultOrCustomModel( CEILING_TURRET_MODEL ) );	
 	PrecacheModel( CEILING_TURRET_GLOW_SPRITE );
 
 	// Activities
@@ -347,7 +347,7 @@ void CNPC_CeilingTurret::Spawn( void )
 { 
 	Precache();
 
-	SetModel( CEILING_TURRET_MODEL );
+	SetModel( DefaultOrCustomModel( CEILING_TURRET_MODEL ) );
 	
 	BaseClass::Spawn();
 
diff --git a/sp/src/game/server/hl2/npc_turret_ground.cpp b/sp/src/game/server/hl2/npc_turret_ground.cpp
index 8ffd37df..c7dceeae 100644
--- a/sp/src/game/server/hl2/npc_turret_ground.cpp
+++ b/sp/src/game/server/hl2/npc_turret_ground.cpp
@@ -69,7 +69,7 @@ END_DATADESC()
 void CNPC_GroundTurret::Precache( void )
 {
 	PrecacheModel( GROUNDTURRET_BEAM_SPRITE );
-	PrecacheModel( "models/combine_turrets/ground_turret.mdl" );
+	PrecacheModel( DefaultOrCustomModel( "models/combine_turrets/ground_turret.mdl" ) );
 
 	PrecacheScriptSound( "NPC_CeilingTurret.Deploy" );
 	m_ShotSounds = PrecacheScriptSound( "NPC_FloorTurret.ShotSounds" );
@@ -88,7 +88,7 @@ void CNPC_GroundTurret::Spawn( void )
 {
 	Precache();
 
-	UTIL_SetModel( this, "models/combine_turrets/ground_turret.mdl" );
+	UTIL_SetModel( this, DefaultOrCustomModel( "models/combine_turrets/ground_turret.mdl" ) );
 
 	SetNavType( NAV_FLY );
 	SetSolid( SOLID_VPHYSICS );