diff --git a/Escape-the-Dawn/ComponentFactory.h b/Escape-the-Dawn/ComponentFactory.h
index 7001fd3..4596c0b 100644
--- a/Escape-the-Dawn/ComponentFactory.h
+++ b/Escape-the-Dawn/ComponentFactory.h
@@ -11,7 +11,7 @@ struct Component;
 #define REGISTER_COMPONENT(NAME, TYPE) \
 	static ComponentRegistrar<TYPE> registrar(NAME);
 
-template<class T>
+template <typename T>
 class ComponentRegistrar
 {
 public:
diff --git a/Escape-the-Dawn/Escape-the-Dawn.vcxproj b/Escape-the-Dawn/Escape-the-Dawn.vcxproj
index 25fbc2c..43a3f9d 100644
--- a/Escape-the-Dawn/Escape-the-Dawn.vcxproj
+++ b/Escape-the-Dawn/Escape-the-Dawn.vcxproj
@@ -90,6 +90,8 @@
   <ItemGroup>
     <ClCompile Include="main.cpp" />
     <ClCompile Include="Renderer.cpp" />
+    <ClCompile Include="Systems\CollisionSystem.cpp" />
+    <ClCompile Include="World.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="Component.h" />
@@ -99,6 +101,8 @@
     <ClInclude Include="logging.h" />
     <ClInclude Include="glerror.h" />
     <ClInclude Include="Renderer.h" />
+    <ClInclude Include="System.h" />
+    <ClInclude Include="Systems\CollisionSystem.h" />
     <ClInclude Include="World.h" />
   </ItemGroup>
   <ItemGroup>
diff --git a/Escape-the-Dawn/Escape-the-Dawn.vcxproj.filters b/Escape-the-Dawn/Escape-the-Dawn.vcxproj.filters
index cf68ad5..5b0a008 100644
--- a/Escape-the-Dawn/Escape-the-Dawn.vcxproj.filters
+++ b/Escape-the-Dawn/Escape-the-Dawn.vcxproj.filters
@@ -18,6 +18,8 @@
     </Filter>
     <Filter Include="Source Files\Renderer">
       <UniqueIdentifier>{7abbf0e9-8bda-475e-bf00-a347f396b892}</UniqueIdentifier>
+    <Filter Include="Header Files\Systems">
+      <UniqueIdentifier>{aca68cba-a16a-4975-8ff3-4d56b88373a1}</UniqueIdentifier>
     </Filter>
     <Filter Include="Header Files\Renderer">
       <UniqueIdentifier>{091f6f01-79ab-4a49-9639-c7185e89c84e}</UniqueIdentifier>
@@ -32,6 +34,11 @@
     </ClCompile>
     <ClCompile Include="Renderer.cpp">
       <Filter>Source Files\Renderer</Filter>
+    <ClCompile Include="World.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="Systems\CollisionSystem.cpp">
+      <Filter>Source Files</Filter>
     </ClCompile>
   </ItemGroup>
   <ItemGroup>
@@ -56,6 +63,12 @@
     <ClInclude Include="ComponentFactory.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="System.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="Systems\CollisionSystem.h">
+      <Filter>Header Files\Systems</Filter>
+    </ClInclude>
     <ClInclude Include="Renderer.h">
       <Filter>Header Files\Renderer</Filter>
     </ClInclude>
diff --git a/Escape-the-Dawn/System.h b/Escape-the-Dawn/System.h
new file mode 100644
index 0000000..4ea04a1
--- /dev/null
+++ b/Escape-the-Dawn/System.h
@@ -0,0 +1,20 @@
+#ifndef System_h__
+#define System_h__
+
+#include "Entity.h"
+
+class World;
+
+class System
+{
+public:
+	System(World* world) : m_World(world) { }
+	virtual ~System() { }
+
+	virtual void Update(double dt, EntityID entity, EntityID parent) = 0;
+
+protected:
+	World* m_World;
+};
+
+#endif // System_h__
\ No newline at end of file
diff --git a/Escape-the-Dawn/Systems/CollisionSystem.cpp b/Escape-the-Dawn/Systems/CollisionSystem.cpp
new file mode 100644
index 0000000..5670652
--- /dev/null
+++ b/Escape-the-Dawn/Systems/CollisionSystem.cpp
@@ -0,0 +1,16 @@
+#include "CollisionSystem.h"
+#include "World.h"
+
+void Systems::Collision::Update(double dt, EntityID entity, EntityID parent)
+{
+	if (parent != 0)
+	{
+		auto transform = m_World->GetComponent<Components::Transform>(entity, "Transform");
+		auto parentTransform = m_World->GetComponent<Components::Transform>(parent, "Transform");
+
+		transform->Position[0] += parentTransform->Position[0];
+		transform->Position[1] += parentTransform->Position[1];
+		transform->Position[2] += parentTransform->Position[2];
+	}
+	LOG_INFO("Updating entity %i with parent %i", entity, parent);
+}
diff --git a/Escape-the-Dawn/Systems/CollisionSystem.h b/Escape-the-Dawn/Systems/CollisionSystem.h
new file mode 100644
index 0000000..c5c1bdd
--- /dev/null
+++ b/Escape-the-Dawn/Systems/CollisionSystem.h
@@ -0,0 +1,23 @@
+#ifndef CollisionSystem_h__
+#define CollisionSystem_h__
+
+#include "System.h"
+#include "logging.h"
+
+#include "Components/Transform.h"
+
+
+namespace Systems
+{
+
+class Collision : public System
+{
+public:
+	Collision(World* world) : System(world) { }
+
+	void Update(double dt, EntityID entity, EntityID parent) override;
+};
+
+}
+
+#endif // CollisionSystem_h__
diff --git a/Escape-the-Dawn/World.cpp b/Escape-the-Dawn/World.cpp
new file mode 100644
index 0000000..fe130a8
--- /dev/null
+++ b/Escape-the-Dawn/World.cpp
@@ -0,0 +1,87 @@
+#include "World.h"
+
+void World::RecycleEntityID(EntityID id)
+{
+	m_RecycledEntityIDs.push(id);
+}
+
+EntityID World::GenerateEntityID()
+{
+	if (!m_RecycledEntityIDs.empty()) {
+		EntityID id = m_RecycledEntityIDs.top();
+		m_RecycledEntityIDs.pop();
+		return id;
+	} else {
+		return ++m_LastEntityID;
+	}
+}
+
+void World::RecursiveUpdate(std::shared_ptr<System> system, double dt, EntityID parentEntity)
+{
+	for (auto pair : m_EntityParents) {
+		EntityID child = pair.first;
+		EntityID parent = pair.second;
+
+		if (parent == parentEntity)	{
+			system->Update(dt, child, parent);
+			RecursiveUpdate(system, dt, child);
+		}
+	}
+}
+
+void World::Update(double dt)
+{
+	for (auto system : m_Systems) {
+		RecursiveUpdate(system, dt, 0);
+	}
+}
+
+void World::AddSystem(System* system)
+{
+
+}
+
+//std::vector<EntityID> GetEntityChildren(EntityID entity);
+//{
+//	std::vector<EntityID> children;
+//	auto range = m_SceneGraph.equal_range(entity);
+//	for (auto it = range.first; it != range.second; ++it)
+//		children.push_back(it->second);
+//	return children;
+//}
+
+EntityID World::GetEntityParent(EntityID entity)
+{
+	auto it = m_EntityParents.find(entity);
+	return it == m_EntityParents.end() ? 0 : it->second;
+}
+
+bool World::ValidEntity(EntityID entity)
+{
+	return m_EntityParents.find(entity) != m_EntityParents.end();
+}
+
+void World::RemoveEntity(EntityID entity)
+{
+	m_EntityParents.erase(entity);
+	RecycleEntityID(entity);
+}
+
+EntityID World::CreateEntity(EntityID parent /*= 0*/)
+{
+	EntityID newEntity = GenerateEntityID();
+	m_EntityParents.insert(std::pair<EntityID, EntityID>(newEntity, parent));
+	return newEntity;
+}
+
+World::~World()
+{
+
+}
+
+World::World()
+{
+	m_LastEntityID = 0;
+
+	m_Systems.push_back(std::make_shared<Systems::Collision>(this));
+}
\ No newline at end of file
diff --git a/Escape-the-Dawn/World.h b/Escape-the-Dawn/World.h
index 9f00114..1dec1c5 100644
--- a/Escape-the-Dawn/World.h
+++ b/Escape-the-Dawn/World.h
@@ -9,79 +9,60 @@
 #include "Entity.h"
 #include "Component.h"
 #include "ComponentFactory.h"
-//#include "Components/Transform.h"
+#include "System.h"
+#include "Systems/CollisionSystem.h"
 
 class World
 {
 public:
-	World()
-	{
-		m_LastEntityID = 0;
-	}
+	World();
+	~World();
 
-	EntityID CreateEntity(EntityID parent = 0)
-	{
-		EntityID newEntity = GenerateEntityID();
-		m_SceneGraph.insert(std::pair<EntityID, EntityID>(newEntity, parent));
-		return newEntity;
-	}
+	EntityID CreateEntity(EntityID parent = 0);
 
-	void RemoveEntity(EntityID entity)
-	{
-		m_SceneGraph.erase(entity);
-		RecycleEntityID(entity);
-	}
+	void RemoveEntity(EntityID entity);
 
-	bool ValidEntity(EntityID entity)
-	{
-		return m_SceneGraph.find(entity) != m_SceneGraph.end();
-	}
+	bool ValidEntity(EntityID entity);
 
-	EntityID GetEntityParent(EntityID entity)
-	{
-		auto it = m_SceneGraph.find(entity);
-		return it == m_SceneGraph.end() ? 0 : it->second;
-	}
+	EntityID GetEntityParent(EntityID entity);
 
-	std::shared_ptr<Component> AddComponent(EntityID entity, std::string componentType)
+	template <class T>
+	std::shared_ptr<T> AddComponent(EntityID entity, std::string componentType)
 	{
-		std::shared_ptr<Component> component = ComponentFactory::Instance()->Create(componentType);
+		std::shared_ptr<T> component = std::static_pointer_cast<T>(ComponentFactory::Instance()->Create(componentType));
 		m_ComponentsOfType[componentType].push_back(component);
 		m_EntityComponents[entity][componentType] = component;
+		return component;
 	}
 
-	/*std::vector<EntityID> GetEntityChildren(EntityID entity)
+	template <class T>
+	std::shared_ptr<T> GetComponent(EntityID entity, std::string componentType)
 	{
-		std::vector<EntityID> children;
-		auto range = m_SceneGraph.equal_range(entity);
-		for (auto it = range.first; it != range.second; ++it)
-			children.push_back(it->second);
-		return children;
-	}*/
+		return std::static_pointer_cast<T>(m_EntityComponents[entity][componentType]);
+	}
+
+	/*std::vector<EntityID> GetEntityChildren(EntityID entity);*/
+
+	void AddSystem(System* system);
+
+	// Recursively update through the scene graph 
+	void Update(double dt);
+
+	void RecursiveUpdate(std::shared_ptr<System> system, double dt, EntityID parentEntity);
 
 private:
 	EntityID m_LastEntityID;
 	std::stack<EntityID> m_RecycledEntityIDs;
-	// A map of child entities to parent entities
-	std::unordered_map<EntityID, EntityID> m_SceneGraph; 
+	// A bottom to top tree. A map of child entities to parent entities.
+	std::unordered_map<EntityID, EntityID> m_EntityParents;
+	
 	std::unordered_map<std::string, std::vector<std::shared_ptr<Component>>> m_ComponentsOfType;
 	std::unordered_map<EntityID, std::map<std::string, std::shared_ptr<Component>>> m_EntityComponents;
+	std::vector<std::shared_ptr<System>> m_Systems;
 
-	EntityID GenerateEntityID()
-	{
-		if (!m_RecycledEntityIDs.empty()) {
-			EntityID id = m_RecycledEntityIDs.top();
-			m_RecycledEntityIDs.pop();
-			return id;
-		} else {
-			return ++m_LastEntityID;
-		}
-	}
+	EntityID GenerateEntityID();
 
-	void RecycleEntityID(EntityID id)
-	{
-		m_RecycledEntityIDs.push(id);
-	}
+	void RecycleEntityID(EntityID id);
 };
 
 #endif // World_h__
\ No newline at end of file
diff --git a/Escape-the-Dawn/logging.h b/Escape-the-Dawn/logging.h
index e2a7b7f..e23be53 100644
--- a/Escape-the-Dawn/logging.h
+++ b/Escape-the-Dawn/logging.h
@@ -49,7 +49,7 @@ static void _LOG(_LOG_LEVEL logLevel, char* file, char* func, unsigned int line,
 	char message[512];
 	va_list args;
 	va_start(args, format);
-	vsnprintf(message, 512, format, args);
+	vsnprintf_s(message, 512, format, args);
 	va_end(args);
 
 	if (logLevel == LOG_LEVEL_ERROR)
diff --git a/Escape-the-Dawn/main.cpp b/Escape-the-Dawn/main.cpp
index e67053c..c9a4f93 100644
--- a/Escape-the-Dawn/main.cpp
+++ b/Escape-the-Dawn/main.cpp
@@ -9,12 +9,34 @@
 #include "logging.h"
 #include "glerror.h"
 
+#include "World.h"
+
 GLFWwindow* window;
 GLint glVersion[2];
 GLchar* glVendor;
 
 int main(int argc, char* argv[])
 {
+	World world;
+
+	EntityID ent1 = world.CreateEntity();
+	auto t1 = world.AddComponent<Components::Transform>(ent1, "Transform");
+	t1->Position[0] = 1.0f;
+	t1->Position[1] = 1.0f;
+	t1->Position[2] = 1.0f;
+	EntityID ent2 = world.CreateEntity(ent1);
+	auto t2 = world.AddComponent<Components::Transform>(ent2, "Transform");
+	t2->Position[0] = 1.0f;
+	t2->Position[1] = 1.0f;
+	t2->Position[2] = 1.0f;
+
+	world.Update(0.0);
+
+	LOG_INFO("ent1: %f %f %f", t1->Position[0], t1->Position[1], t1->Position[2]);
+	LOG_INFO("ent2: %f %f %f", t2->Position[0], t2->Position[1], t2->Position[2]);
+
+	return 0;
+
 	// Initialize GLFW
 	if (!glfwInit())
 	{
diff --git a/Tests/Tests.vcxproj b/Tests/Tests.vcxproj
index c013dba..b6294b2 100644
--- a/Tests/Tests.vcxproj
+++ b/Tests/Tests.vcxproj
@@ -80,6 +80,16 @@
   <ItemGroup>
     <ClCompile Include="main.cpp" />
   </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\Escape-the-Dawn\Escape-the-Dawn.vcxproj">
+      <Project>{fe405cfa-8fce-4867-92cf-797e73b36482}</Project>
+      <Private>true</Private>
+      <ReferenceOutputAssembly>true</ReferenceOutputAssembly>
+      <CopyLocalSatelliteAssemblies>false</CopyLocalSatelliteAssemblies>
+      <LinkLibraryDependencies>true</LinkLibraryDependencies>
+      <UseLibraryDependencyInputs>false</UseLibraryDependencyInputs>
+    </ProjectReference>
+  </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
diff --git a/Tests/main.cpp b/Tests/main.cpp
index 6a335d1..bc0a4f0 100644
--- a/Tests/main.cpp
+++ b/Tests/main.cpp
@@ -20,6 +20,27 @@ BOOST_AUTO_TEST_CASE(Parenting)
 	BOOST_CHECK(world.GetEntityParent(ent2) == ent1);
 }
 
+BOOST_AUTO_TEST_CASE(SceneGraphTraversal)
+{
+	World world;
+
+	EntityID ent1 = world.CreateEntity();
+	auto t1 = world.AddComponent<Components::Transform>(ent1, "Transform");
+	t1->Position[0] = 1.0f;
+	t1->Position[1] = 1.0f;
+	t1->Position[2] = 1.0f;
+	EntityID ent2 = world.CreateEntity(ent1);
+	auto t2 = world.AddComponent<Components::Transform>(ent2, "Transform");
+	t2->Position[0] = 1.0f;
+	t2->Position[1] = 1.0f;
+	t2->Position[2] = 1.0f;
+
+	world.Update(0.0);
+
+	LOG_INFO("ent1: %f %f %f", t1->Position[0], t1->Position[1], t1->Position[2]);
+	LOG_INFO("ent2: %f %f %f", t2->Position[0], t2->Position[1], t2->Position[2]);
+}
+
 BOOST_AUTO_TEST_CASE(Recycling)
 {
 	World world;