diff --git a/include/ishaders.h b/include/ishaders.h
index 64f6e04d58..82a131f781 100644
--- a/include/ishaders.h
+++ b/include/ishaders.h
@@ -414,9 +414,6 @@ class MaterialManager
      */
     virtual void setActiveShaderUpdates(bool val) = 0;
 
-  virtual void attach(ModuleObserver& observer) = 0;
-  virtual void detach(ModuleObserver& observer) = 0;
-
   virtual void setLightingEnabled(bool enabled) = 0;
 
   virtual const char* getTexturePrefix() const = 0;
diff --git a/plugins/shaders/Doom3ShaderSystem.cpp b/plugins/shaders/Doom3ShaderSystem.cpp
index e602514b0c..b547259e79 100644
--- a/plugins/shaders/Doom3ShaderSystem.cpp
+++ b/plugins/shaders/Doom3ShaderSystem.cpp
@@ -46,7 +46,6 @@ Doom3ShaderSystem::Doom3ShaderSystem() :
     _defLoader(std::bind(&Doom3ShaderSystem::loadMaterialFiles, this)),
 	_enableActiveUpdates(true),
 	_realised(false),
-	_observers(getName()),
 	_currentOperation(nullptr)
 {}
 
@@ -120,7 +119,6 @@ void Doom3ShaderSystem::realise()
         _defLoader.start();
 
 		_signalDefsLoaded.emit();
-		_observers.realise();
 		_realised = true;
 	}
 }
@@ -130,7 +128,6 @@ void Doom3ShaderSystem::unrealise()
 	if (_realised)
 	{
 		_signalDefsUnloaded.emit();
-		_observers.unrealise();
 		freeShaders();
 		_realised = false;
 	}
@@ -208,26 +205,6 @@ void Doom3ShaderSystem::foreachShaderName(const ShaderNameCallback& callback)
 	_library->foreachShaderName(callback);
 }
 
-void Doom3ShaderSystem::attach(ModuleObserver& observer)
-{
-	_observers.attach(observer);
-
-	if (_realised)
-	{
-		observer.realise();
-	}
-}
-
-void Doom3ShaderSystem::detach(ModuleObserver& observer)
-{
-	if (_realised)
-	{
-		observer.unrealise();
-	}
-
-	_observers.detach(observer);
-}
-
 void Doom3ShaderSystem::setLightingEnabled(bool enabled)
 {
     ensureDefsLoaded();
diff --git a/plugins/shaders/Doom3ShaderSystem.h b/plugins/shaders/Doom3ShaderSystem.h
index 8ff6ce0252..b4de396aef 100644
--- a/plugins/shaders/Doom3ShaderSystem.h
+++ b/plugins/shaders/Doom3ShaderSystem.h
@@ -7,7 +7,6 @@
 #include "icommandsystem.h"
 
 #include <functional>
-#include "moduleobservers.h"
 
 #include "ShaderLibrary.h"
 #include "TableDefinition.h"
@@ -44,10 +43,6 @@ class Doom3ShaderSystem :
 	// TRUE if the material files have been parsed
 	bool _realised;
 
-	// The observers that are attached to this system. These get
-	// notified upon realisation of this class.
-	ModuleObservers _observers;
-
 	// Signals for module subscribers
 	sigc::signal<void> _signalDefsLoaded;
 	sigc::signal<void> _signalDefsUnloaded;
@@ -96,9 +91,6 @@ class Doom3ShaderSystem :
 		_enableActiveUpdates = v;
 	}
 
-	void attach(ModuleObserver& observer) override;
-	void detach(ModuleObserver& observer) override;
-
     void setLightingEnabled(bool enabled) override;
 
     const char* getTexturePrefix() const override;
diff --git a/radiant/render/OpenGLRenderSystem.cpp b/radiant/render/OpenGLRenderSystem.cpp
index 54133dc5dc..3c0fc9ccd7 100644
--- a/radiant/render/OpenGLRenderSystem.cpp
+++ b/radiant/render/OpenGLRenderSystem.cpp
@@ -48,7 +48,10 @@ OpenGLRenderSystem::OpenGLRenderSystem() :
 	// hence it will be attached in initialiseModule().
     if (module::ModuleRegistry::Instance().moduleExists(MODULE_SHADERSYSTEM))
 	{
-		GlobalMaterialManager().attach(*this);
+		_materialDefsLoaded = GlobalMaterialManager().signal_DefsLoaded().connect(
+			sigc::mem_fun(*this, &OpenGLRenderSystem::realise));
+		_materialDefsUnloaded = GlobalMaterialManager().signal_DefsUnloaded().connect(
+			sigc::mem_fun(*this, &OpenGLRenderSystem::unrealise));
 	}
 
     // If the openGL module is already initialised and a shared context is created
@@ -62,12 +65,8 @@ OpenGLRenderSystem::OpenGLRenderSystem() :
 
 OpenGLRenderSystem::~OpenGLRenderSystem()
 {
-	// The static default rendersystem won't use this, it will detach itself
-	// in the shutdownModule() method.
-    if (module::ModuleRegistry::Instance().moduleExists(MODULE_SHADERSYSTEM))
-	{
-		GlobalMaterialManager().detach(*this);
-	}
+	_materialDefsLoaded.disconnect();
+	_materialDefsUnloaded.disconnect();
 }
 
 ShaderPtr OpenGLRenderSystem::capture(const std::string& name)
@@ -524,7 +523,10 @@ void OpenGLRenderSystem::initialiseModule(const ApplicationContext& ctx)
 {
 	rMessage() << getName() << "::initialiseModule called." << std::endl;
 
-	GlobalMaterialManager().attach(*this);
+	_materialDefsLoaded = GlobalMaterialManager().signal_DefsLoaded().connect(
+		sigc::mem_fun(*this, &OpenGLRenderSystem::realise));
+	_materialDefsUnloaded = GlobalMaterialManager().signal_DefsUnloaded().connect(
+		sigc::mem_fun(*this, &OpenGLRenderSystem::unrealise));
 
 	// greebo: Don't realise the module yet, this must wait
 	// until the shared GL context has been created (this
@@ -533,7 +535,8 @@ void OpenGLRenderSystem::initialiseModule(const ApplicationContext& ctx)
 
 void OpenGLRenderSystem::shutdownModule()
 {
-	GlobalMaterialManager().detach(*this);
+	_materialDefsLoaded.disconnect();
+	_materialDefsUnloaded.disconnect();
 }
 
 // Define the static ShaderCache module
diff --git a/radiant/render/OpenGLRenderSystem.h b/radiant/render/OpenGLRenderSystem.h
index 5f48b95052..5721a4a609 100644
--- a/radiant/render/OpenGLRenderSystem.h
+++ b/radiant/render/OpenGLRenderSystem.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include "irender.h"
+#include <sigc++/connection.h>
 #include <map>
 #include "imodule.h"
 #include "backend/OpenGLStateManager.h"
@@ -20,8 +21,7 @@ typedef std::shared_ptr<GLProgramFactory> GLProgramFactoryPtr;
  */
 class OpenGLRenderSystem
 : public RenderSystem,
-  public OpenGLStateManager,
-  public ModuleObserver
+  public OpenGLStateManager
 {
 private:
 	// Map of named Shader objects
@@ -51,6 +51,9 @@ class OpenGLRenderSystem
 
 	sigc::signal<void> _sigExtensionsInitialised;
 
+	sigc::connection _materialDefsLoaded;
+	sigc::connection _materialDefsUnloaded;
+
 private:
 	void propagateLightChangedFlagToAllLights();