diff --git a/source/graphics/GameView.cpp b/source/graphics/GameView.cpp
index d43bb48888..16c69713e5 100644
--- a/source/graphics/GameView.cpp
+++ b/source/graphics/GameView.cpp
@@ -1,45 +1,41 @@
-
-
 #include "precompiled.h"
 
-#include "Terrain.h"
-#include "renderer/Renderer.h"
 #include "GameView.h"
-#include "ps/Game.h"
-#include "Camera.h"
-#include "ps/Interact.h"
 
-#include "maths/Matrix3D.h"
-#include "maths/MathUtil.h"
-#include "renderer/Renderer.h"
-#include "Terrain.h"
-#include "LightEnv.h"
-#include "HFTracer.h"
-#include "TextureManager.h"
-#include "ObjectManager.h"
-#include "simulation/LOSManager.h"
-#include "simulation/EntityOrders.h"
-#include "maths/Bound.h"
-#include "ps/Pyrogenesis.h"
-#include "ps/Hotkey.h"
-#include "ps/ConfigDB.h"
-#include "ps/Loader.h"
-#include "ps/Profile.h"
-#include "ps/LoaderThunks.h"
-#include "ps/Globals.h"
-#include "renderer/WaterManager.h"
-#include "renderer/SkyManager.h"
-#include "graphics/UnitManager.h"
+#include "graphics/Camera.h"
+#include "graphics/HFTracer.h"
+#include "graphics/LightEnv.h"
+#include "graphics/Model.h"
+#include "graphics/ObjectManager.h"
 #include "graphics/Patch.h"
-
-#include "maths/Quaternion.h"
-#include "Unit.h"
-#include "Model.h"
-#include "simulation/Projectile.h"
-
+#include "graphics/Terrain.h"
+#include "graphics/TextureManager.h"
+#include "graphics/Unit.h"
+#include "graphics/UnitManager.h"
 #include "lib/input.h"
 #include "lib/lib.h"
 #include "lib/timer.h"
+#include "maths/Bound.h"
+#include "maths/MathUtil.h"
+#include "maths/Matrix3D.h"
+#include "maths/Quaternion.h"
+#include "ps/ConfigDB.h"
+#include "ps/Game.h"
+#include "ps/Globals.h"
+#include "ps/Hotkey.h"
+#include "ps/Interact.h"
+#include "ps/Loader.h"
+#include "ps/LoaderThunks.h"
+#include "ps/Profile.h"
+#include "ps/Pyrogenesis.h"
+#include "renderer/Renderer.h"
+#include "renderer/Renderer.h"
+#include "renderer/SkyManager.h"
+#include "renderer/WaterManager.h"
+#include "simulation/Entity.h"
+#include "simulation/EntityOrders.h"
+#include "simulation/LOSManager.h"
+#include "simulation/Projectile.h"
 
 float g_MaxZoomHeight=350.0f;	//note:  Max terrain height is this minus YMinOffset
 float g_YMinOffset=15.0f;
diff --git a/source/graphics/GameView.h b/source/graphics/GameView.h
index a92d55d367..4ae857e7b2 100644
--- a/source/graphics/GameView.h
+++ b/source/graphics/GameView.h
@@ -7,7 +7,6 @@ extern float g_YMinOffset;
 
 #include "Camera.h"
 #include "CinemaTrack.h"
-#include "ModelDef.h"
 #include "maths/Vector3D.h"
 #include "LightEnv.h"
 #include "scripting/ScriptableObject.h"
diff --git a/source/pch/atlas/precompiled.h b/source/pch/atlas/precompiled.h
index fa04605c7e..18a6cda481 100644
--- a/source/pch/atlas/precompiled.h
+++ b/source/pch/atlas/precompiled.h
@@ -2,4 +2,11 @@
 
 // Atlas-specific PCH:
 
+#if HAVE_PCH
+
 #include "tools/atlas/GameInterface/Messages.h"
+#include "ps/CStr.h"
+#include "ps/Errors.h"
+#include "graphics/GameView.h"
+
+#endif // HAVE_PCH
diff --git a/source/pch/engine/precompiled.h b/source/pch/engine/precompiled.h
index d12173bda0..3b7df3c568 100644
--- a/source/pch/engine/precompiled.h
+++ b/source/pch/engine/precompiled.h
@@ -4,6 +4,8 @@
 
 #include "ps/Pyrogenesis.h"	// MICROLOG and old error system
 
+#if HAVE_PCH
+
 // some other external libraries that are used in several places:
 // .. CStr is included very frequently, so a reasonable amount of time is
 //    saved by including it here. (~10% in a full rebuild, as of r2365)
@@ -11,3 +13,5 @@
 #include "scripting/SpiderMonkey.h"
 #include <boost/shared_ptr.hpp>
 #include <boost/weak_ptr.hpp>
+
+#endif // HAVE_PCH
diff --git a/source/ps/CConsole.cpp b/source/ps/CConsole.cpp
index f01fbc8eb6..baa48bbe06 100644
--- a/source/ps/CConsole.cpp
+++ b/source/ps/CConsole.cpp
@@ -17,6 +17,7 @@
 #include "ps/Network/Server.h"
 #include "ps/Pyrogenesis.h"
 #include "scripting/ScriptingHost.h"
+#include "simulation/Entity.h"
 
 CConsole* g_Console = 0;
 
diff --git a/source/ps/Interact.cpp b/source/ps/Interact.cpp
index 9709da4a13..604c988368 100644
--- a/source/ps/Interact.cpp
+++ b/source/ps/Interact.cpp
@@ -1,12 +1,14 @@
 #include "precompiled.h"
 
-#include "CConsole.h"
-#include "Game.h"
-#include "Hotkey.h"
 #include "Interact.h"
+
+#include "ps/CConsole.h"
+#include "ps/Game.h"
+#include "ps/Hotkey.h"
 #include "graphics/GameView.h"
 #include "graphics/HFTracer.h"
 #include "graphics/Model.h"
+#include "graphics/ModelDef.h"
 #include "graphics/Terrain.h"
 #include "graphics/Unit.h"
 #include "graphics/UnitManager.h"
@@ -20,11 +22,15 @@
 #include "ps/Network/NetMessage.h"
 #include "ps/Player.h"
 #include "ps/VFSUtil.h"
+#include "ps/World.h"
 #include "renderer/Renderer.h"
 #include "scripting/GameEvents.h"
 #include "simulation/BaseEntityCollection.h"
 #include "simulation/BoundingObjects.h"
+#include "simulation/Collision.h"
+#include "simulation/Entity.h"
 #include "simulation/EntityFormation.h"
+#include "simulation/EntityManager.h"
 #include "simulation/FormationManager.h"
 #include "simulation/Simulation.h"
 
diff --git a/source/ps/Interact.h b/source/ps/Interact.h
index b6b6f1617a..0cf1207102 100644
--- a/source/ps/Interact.h
+++ b/source/ps/Interact.h
@@ -9,15 +9,15 @@
 #include <vector>
 
 #include "Singleton.h"
-#include "simulation/Entity.h"
-#include "simulation/EntityManager.h"
-#include "simulation/EntityMessage.h"
-#include "simulation/Collision.h"
-#include "simulation/Scheduler.h"
-#include "graphics/Camera.h"
+#include "simulation/EntityHandles.h"
+#include "ps/Vector2D.h"
 #include "lib/input.h"
 #include "lib/res/handle.h"
 
+class CVector3D;
+class CUnit;
+class CBoundingObject;
+
 #define MAX_BOOKMARKS 10
 #define MAX_GROUPS    20
 
diff --git a/source/ps/Network/JSEvents.h b/source/ps/Network/JSEvents.h
index b2a9211f57..493af92f69 100644
--- a/source/ps/Network/JSEvents.h
+++ b/source/ps/Network/JSEvents.h
@@ -2,6 +2,7 @@
 #define _Network_JSEvents_H
 
 #include "ServerSession.h"
+#include "scripting/DOMEvent.h"
 
 enum ENetworkJSEvents
 {
diff --git a/source/ps/Player.h b/source/ps/Player.h
index e4ccf811b9..b0ab1ef3b9 100644
--- a/source/ps/Player.h
+++ b/source/ps/Player.h
@@ -5,9 +5,9 @@
 #include "scripting/SynchedJSObject.h"
 #include "scripting/ScriptableObject.h"
 #include "scripting/ScriptCustomTypes.h" 
-#include "simulation/EntityHandles.h"
 
 class CNetMessage;
+class HEntity;
 
 typedef SColour SPlayerColour;
 
diff --git a/source/ps/scripting/JSInterface_Selection.cpp b/source/ps/scripting/JSInterface_Selection.cpp
index 22d2c8e939..c0a71f7c47 100644
--- a/source/ps/scripting/JSInterface_Selection.cpp
+++ b/source/ps/scripting/JSInterface_Selection.cpp
@@ -6,6 +6,7 @@
 #include "JSInterface_Selection.h"
 #include "ps/scripting/JSCollection.h"
 #include "ps/Interact.h"
+#include "simulation/Entity.h"
 
 JSBool JSI_Selection::getSelection( JSContext* UNUSED(cx), JSObject* UNUSED(obj),
 	jsval UNUSED(id), jsval* vp )
diff --git a/source/scripting/ScriptableComplex.cpp b/source/scripting/ScriptableComplex.cpp
index d696e1fbc4..613e0f6df9 100644
--- a/source/scripting/ScriptableComplex.cpp
+++ b/source/scripting/ScriptableComplex.cpp
@@ -1,6 +1,8 @@
 #include "precompiled.h"
 #include "ScriptableComplex.h"
 
+#include "lib/allocators.h"
+
 // suballocator for CJSComplex.m_Properties elements
 static Bucket bucket;
 // HACK: it needs to be created/destroyed; since there is no
diff --git a/source/scripting/ScriptableComplex.h b/source/scripting/ScriptableComplex.h
index 84e48a0f47..891181a9f6 100644
--- a/source/scripting/ScriptableComplex.h
+++ b/source/scripting/ScriptableComplex.h
@@ -7,8 +7,6 @@
 #include "simulation/ScriptObject.h"
 #include "JSConversions.h"
 
-#include "lib/allocators.h"
-
 #include <set>
 
 #ifndef SCRIPTABLE_COMPLEX_INCLUDED
diff --git a/source/simulation/Aura.cpp b/source/simulation/Aura.cpp
index 569dc6bee8..9c77b9628c 100644
--- a/source/simulation/Aura.cpp
+++ b/source/simulation/Aura.cpp
@@ -1,9 +1,11 @@
 #include "precompiled.h"
-#include "Aura.h"
-#include "EntityManager.h"
-#include <algorithm>
 
-using namespace std;
+#include "Aura.h"
+
+#include "EntityManager.h"
+#include "Entity.h"
+
+#include <algorithm>
 
 CAura::CAura( JSContext* cx, CEntity* source, CStrW& name, float radius, size_t tickRate, JSObject* handler )
 		: m_cx(cx), m_source(source), m_name(name), m_radius(radius), m_handler(handler),
@@ -19,13 +21,13 @@ CAura::~CAura()
 
 void CAura::Update( size_t timestep )
 {
-	vector<CEntity*> inRange;
+	std::vector<CEntity*> inRange;
 	CVector3D pos = m_source->m_position;
 	g_EntityManager.GetInRange( pos.X, pos.Z, m_radius, inRange );
 
-	vector<CEntity*> prevInfluenced, curInfluenced, entered, exited;
+	std::vector<CEntity*> prevInfluenced, curInfluenced, entered, exited;
 
-	for( vector<HEntity>::iterator it = m_influenced.begin(); it != m_influenced.end(); it++ )
+	for( std::vector<HEntity>::iterator it = m_influenced.begin(); it != m_influenced.end(); it++ )
 	{
 		CEntity* ent = *it;
 		if( ent->m_extant )
@@ -36,7 +38,7 @@ void CAura::Update( size_t timestep )
 
 	m_influenced.clear();
 
-	for( vector<CEntity*>::iterator it = inRange.begin(); it != inRange.end(); it++ )
+	for( std::vector<CEntity*>::iterator it = inRange.begin(); it != inRange.end(); it++ )
 	{
 		CEntity* ent = *it;
 		if(ent != m_source)
@@ -59,11 +61,11 @@ void CAura::Update( size_t timestep )
 	if( JS_GetUCProperty( m_cx, m_handler, enterName16.c_str(), enterName16.length(), &enterFunction )
 		&& enterFunction != JSVAL_VOID)
 	{
-		back_insert_iterator<vector<CEntity*> > ins( entered );
+		std::back_insert_iterator<std::vector<CEntity*> > ins( entered );
 		set_difference( curInfluenced.begin(), curInfluenced.end(), 
 			prevInfluenced.begin(), prevInfluenced.end(), 
 			ins );
-		for( vector<CEntity*>::iterator it = entered.begin(); it != entered.end(); it++ )
+		for( std::vector<CEntity*>::iterator it = entered.begin(); it != entered.end(); it++ )
 		{
 			argv[0] = OBJECT_TO_JSVAL( (*it)->GetScript() );
 			JS_CallFunctionValue( m_cx, m_handler, enterFunction, 1, argv, &rval );
@@ -78,11 +80,11 @@ void CAura::Update( size_t timestep )
 	if( JS_GetUCProperty( m_cx, m_handler, exitName16.c_str(), exitName16.length(), &exitFunction )
 		&& exitFunction != JSVAL_VOID )
 	{
-		back_insert_iterator<vector<CEntity*> > ins( exited );
+		std::back_insert_iterator<std::vector<CEntity*> > ins( exited );
 		set_difference( prevInfluenced.begin(), prevInfluenced.end(), 
 			curInfluenced.begin(), curInfluenced.end(), 
 			ins );
-		for( vector<CEntity*>::iterator it = exited.begin(); it != exited.end(); it++ )
+		for( std::vector<CEntity*>::iterator it = exited.begin(); it != exited.end(); it++ )
 		{
 			argv[0] = OBJECT_TO_JSVAL( (*it)->GetScript() );
 			JS_CallFunctionValue( m_cx, m_handler, exitFunction, 1, argv, &rval );
@@ -101,7 +103,7 @@ void CAura::Update( size_t timestep )
 		if( JS_GetUCProperty( m_cx, m_handler, tickName16.c_str(), tickName16.length(), &tickFunction )
 			&& tickFunction != JSVAL_VOID )
 		{
-			for( vector<CEntity*>::iterator it = curInfluenced.begin(); it != curInfluenced.end(); it++ )
+			for( std::vector<CEntity*>::iterator it = curInfluenced.begin(); it != curInfluenced.end(); it++ )
 			{
 				argv[0] = OBJECT_TO_JSVAL( (*it)->GetScript() );
 				JS_CallFunctionValue( m_cx, m_handler, tickFunction, 1, argv, &rval );
@@ -124,7 +126,7 @@ void CAura::RemoveAll()
 		&& exitFunction != JSVAL_VOID )
 	{
 		// Call the exit function on everything in our influence
-		for( vector<HEntity>::iterator it = m_influenced.begin(); it != m_influenced.end(); it++ )
+		for( std::vector<HEntity>::iterator it = m_influenced.begin(); it != m_influenced.end(); it++ )
 		{
 			CEntity* ent = *it;
 			if( ent->m_extant )
diff --git a/source/simulation/Aura.h b/source/simulation/Aura.h
index e37643b5c3..99bc4a2ffe 100644
--- a/source/simulation/Aura.h
+++ b/source/simulation/Aura.h
@@ -1,9 +1,10 @@
-#include "Entity.h"
-#include "EntityHandles.h"
-
 #ifndef __AURA_H__
 #define __AURA_H__
 
+#include "EntityHandles.h"
+
+class CEntity;
+
 class CAura
 {
 public:
diff --git a/source/simulation/BaseTech.h b/source/simulation/BaseTech.h
index b863a66b90..5476173158 100644
--- a/source/simulation/BaseTech.h
+++ b/source/simulation/BaseTech.h
@@ -6,7 +6,7 @@
 #define BASETECH_INCLUDED
 
 #include <vector>
-#include "scripting/ScriptableComplex.h"
+#include "scripting/ScriptableObject.h"
 
 class CStr;
 class XMBElement;
diff --git a/source/simulation/Entity.h b/source/simulation/Entity.h
index 52e88e46bd..9173f30c1d 100644
--- a/source/simulation/Entity.h
+++ b/source/simulation/Entity.h
@@ -33,9 +33,9 @@
 #include "EntityOrders.h"
 #include "EntityHandles.h"
 #include "EntityMessage.h"
-#include "EventHandlers.h"
 #include "ScriptObject.h"
 #include "EntitySupport.h"
+#include "scripting/DOMEvent.h"
 
 class CAura;
 class CBaseEntity;
diff --git a/source/simulation/EntityFormation.cpp b/source/simulation/EntityFormation.cpp
index daf5c6e1ed..b44c18a0c4 100644
--- a/source/simulation/EntityFormation.cpp
+++ b/source/simulation/EntityFormation.cpp
@@ -1,5 +1,8 @@
 #include "precompiled.h"
+
 #include "EntityFormation.h"
+
+#include "Entity.h"
 #include "BaseFormationCollection.h"
 #include "FormationManager.h"
 #include "Simulation.h"
diff --git a/source/simulation/EntityFormation.h b/source/simulation/EntityFormation.h
index fa35c05a0f..78508e37eb 100644
--- a/source/simulation/EntityFormation.h
+++ b/source/simulation/EntityFormation.h
@@ -8,11 +8,11 @@
 #define ENTITYFORMATION_INCLUDED
 
 #include "BaseFormation.h"
-#include "EntitySupport.h"
 #include "ps/Vector2D.h"
 
 class CVector2D;
 class CEntity;
+struct CEntityList;
 struct SClassSet;
 
 class CEntityFormation
diff --git a/source/simulation/FormationManager.cpp b/source/simulation/FormationManager.cpp
index 7dd6ab4966..2284953f6e 100644
--- a/source/simulation/FormationManager.cpp
+++ b/source/simulation/FormationManager.cpp
@@ -5,6 +5,7 @@
 #include "ps/CStr.h"
 #include "BaseFormation.h"
 #include "EntityFormation.h"
+#include "EventHandlers.h"
 
 #include "ps/Vector2D.h"
 
diff --git a/source/simulation/ProductionQueue.cpp b/source/simulation/ProductionQueue.cpp
index c1270fe976..1d47c9f78e 100644
--- a/source/simulation/ProductionQueue.cpp
+++ b/source/simulation/ProductionQueue.cpp
@@ -1,6 +1,8 @@
 #include "precompiled.h"
 #include "ProductionQueue.h"
 #include "EntityManager.h"
+#include "EventHandlers.h"
+#include "Entity.h"
 #include <algorithm>
 
 using namespace std;
diff --git a/source/simulation/ProductionQueue.h b/source/simulation/ProductionQueue.h
index 64721212e8..2e90ac876f 100644
--- a/source/simulation/ProductionQueue.h
+++ b/source/simulation/ProductionQueue.h
@@ -1,10 +1,12 @@
-#include "Entity.h"
-#include "EntityHandles.h"
-#include <vector>
-
 #ifndef __PRODUCTIONQUEUE_H__
 #define __PRODUCTIONQUEUE_H__
 
+#include "EntityHandles.h"
+#include "scripting/ScriptableObject.h"
+#include <vector>
+
+class CEntity;
+
 class CProductionItem : public CJSObject<CProductionItem>
 {
 public:
diff --git a/source/simulation/ScriptObject.cpp b/source/simulation/ScriptObject.cpp
index f313060846..3c0aab8d2a 100644
--- a/source/simulation/ScriptObject.cpp
+++ b/source/simulation/ScriptObject.cpp
@@ -111,7 +111,7 @@ bool CScriptObject::DispatchEvent( JSObject* Context, CScriptEvent* evt )
 	return( evt->m_Blocked );
 }
 
-void CScriptObject::Compile( CStrW FileNameTag, CStrW FunctionBody )
+void CScriptObject::Compile( const CStrW& FileNameTag, const CStrW& FunctionBody )
 {
 	if( Function )
 		JS_RemoveRoot( g_ScriptingHost.GetContext(), &Function );
diff --git a/source/simulation/ScriptObject.h b/source/simulation/ScriptObject.h
index 53e61af673..115ed105d3 100644
--- a/source/simulation/ScriptObject.h
+++ b/source/simulation/ScriptObject.h
@@ -6,11 +6,8 @@
 #ifndef SCRIPTOBJECT_INCLUDED
 #define SCRIPTOBJECT_INCLUDED
 
-#include "ps/CStr.h"
-#include "scripting/ScriptingHost.h"
-#include "EntityHandles.h"
-#include "simulation/scripting/JSInterface_Entity.h"
-#include "scripting/DOMEvent.h"
+class CStrW;
+class CScriptEvent;
 
 class CScriptObject
 {
@@ -31,7 +28,7 @@ public:
 	// Initialize in various ways: from a JS function, a string to be compiled, or a jsval containing either.
 	void SetFunction( JSFunction* _Function );
 	void SetJSVal( jsval v );
-	void Compile( CStrW FileNameTag, CStrW FunctionBody );
+	void Compile( const CStrW& FileNameTag, const CStrW& FunctionBody );
 
 	inline bool Defined()
 	{