diff --git a/main.go b/main.go
index 18cfa46..a700f07 100755
--- a/main.go
+++ b/main.go
@@ -22,6 +22,7 @@ func main() {
 	sd := pgo.NewSceneDesc(ts)
 	sd.SetGravity(pgo.NewVec3(0, -9.8, 0))
 	sd.SetCpuDispatcher(pgo.DefaultCpuDispatcherCreate(2, 0).ToCpuDispatcher())
+	sd.SetOnContactCallback()
 
 	s := p.CreateScene(sd)
 	println("Scene:", s)
@@ -63,19 +64,23 @@ func main() {
 
 	ra = dynBox2.ToRigidActor()
 	ra.SetSimFilterData(&fd)
-
 	s.AddActor(dynBox2.ToActor())
 
 	//Add sphere
 	v = pgo.NewVec3(0, 16, 0)
 	tr3 := pgo.NewTransform(v, qID)
 	dynSphere := pgo.CreateDynamic(p, tr3, pgo.NewSphereGeometry(3).ToGeometry(), pMat, 1, shapeOffset)
+
+	ra = dynSphere.ToRigidActor()
+	ra.SetSimFilterData(&fd)
 	s.AddActor(dynSphere.ToActor())
 
 	//Add capsule
 	v = pgo.NewVec3(0, 20, 0)
 	tr4 := pgo.NewTransform(v, qID)
 	dynCapsule := pgo.CreateDynamic(p, tr4, pgo.NewCapsuleGeometry(0.25, 0.5).ToGeometry(), pMat, 1, shapeOffset)
+	ra = dynCapsule.ToRigidActor()
+	ra.SetSimFilterData(&fd)
 	s.AddActor(dynCapsule.ToActor())
 
 	//Add compound shape
@@ -89,6 +94,8 @@ func main() {
 	someShape = pgo.CreateExclusiveShape(dynComp.ToRigidActor(), pgo.NewSphereGeometry(2).ToGeometry(), pMat, pgo.ShapeFlags_eSCENE_QUERY_SHAPE|pgo.ShapeFlags_eSIMULATION_SHAPE|pgo.ShapeFlags_eVISUALIZATION)
 	someShape.SetLocalPose(pgo.NewTransform(pgo.NewVec3(-5, 0, 0), qID))
 
+	ra = dynComp.ToRigidActor()
+	ra.SetSimFilterData(&fd)
 	s.AddActor(dynComp.ToActor())
 
 	//Make some changes and print info
diff --git a/pgo/ccallbacks.go b/pgo/ccallbacks.go
new file mode 100755
index 0000000..912f769
--- /dev/null
+++ b/pgo/ccallbacks.go
@@ -0,0 +1,10 @@
+package pgo
+
+/*
+void goOnContactCallback_cgo(void* pairHeader)
+{
+	void goOnContactCallback(void*);
+	goOnContactCallback(pairHeader);
+}
+*/
+import "C"
diff --git a/pgo/libs/libphysx-c.a b/pgo/libs/libphysx-c.a
index 6681115..7da1bf3 100755
Binary files a/pgo/libs/libphysx-c.a and b/pgo/libs/libphysx-c.a differ
diff --git a/pgo/pgo.go b/pgo/pgo.go
index 64b1508..7b2d7dd 100755
--- a/pgo/pgo.go
+++ b/pgo/pgo.go
@@ -6,8 +6,12 @@ package pgo
 
 #include <wrap.c>
 #include <stdlib.h> //Needed for C.free
+
+//simulation event callbacks forward declarations. Actual definitions MUST be in a go different file
+void goOnContactCallback_cgo(void* pairHeader);
 */
 import "C"
+import "unsafe"
 
 type PvdInstrumentationFlag uint32
 
@@ -99,8 +103,6 @@ func (s *Scene) Simulate(elapsedTime float32) {
 	C.CPxScene_simulate(s.cS, C.float(elapsedTime))
 }
 
-// void CPxScene_advance(CSTRUCT CPxScene*);
-
 func (s *Scene) Collide(elapsedTime float32) {
 	C.CPxScene_collide(s.cS, C.float(elapsedTime))
 }
@@ -203,9 +205,6 @@ func (s *Shape) SetSimulationFilterData(fd *FilterData) {
 	C.CPxShape_setSimulationFilterData(&s.cShape, &fd.cFilterData)
 }
 
-// CPxAPI CSTRUCT CPxFilterData CPxShape_getSimulationFilterData(CSTRUCT CPxShape* cs);
-// CPxAPI void CPxShape_setSimulationFilterData(CSTRUCT CPxShape* cs, CSTRUCT CPxFilterData cfd);
-
 func CreateExclusiveShape(rigidActor RigidActor, geom *Geometry, mat *Material, shapeFlags ShapeFlags) Shape {
 	return Shape{
 		cShape: C.createExclusiveShape(rigidActor.cRa, geom.cG, mat.cM, uint32(shapeFlags)),
@@ -264,6 +263,15 @@ func (sd *SceneDesc) SetCpuDispatcher(cd *CpuDispatcher) {
 	C.CPxSceneDesc_set_cpuDispatcher(sd.cSD, cd.cCpuDisp)
 }
 
+//export goOnContactCallback
+func goOnContactCallback(p unsafe.Pointer) {
+	println("!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!")
+}
+
+func (sd *SceneDesc) SetOnContactCallback() {
+	C.CPxSceneDesc_set_onContactCallback(sd.cSD, (C.CPxonContactCallback)(unsafe.Pointer(C.goOnContactCallback_cgo)))
+}
+
 func NewSceneDesc(ts *TolerancesScale) *SceneDesc {
 	return &SceneDesc{
 		cSD: C.NewCPxSceneDesc(ts.cTolScale),
diff --git a/pgo/physx-c/CPxSceneDesc.h b/pgo/physx-c/CPxSceneDesc.h
index 094a800..221aed4 100755
--- a/pgo/physx-c/CPxSceneDesc.h
+++ b/pgo/physx-c/CPxSceneDesc.h
@@ -13,14 +13,17 @@ extern "C" {
 		void* obj;
 	};
 
+	typedef void (*CPxonContactCallback)(void* pairHeader);
+
 	/// <summary>
-	/// Creates a SceneDesc with a custom filterShader that uses word0/word1 as groups shapes belong to, and word2/word3 as mask on the groups.
+	/// Creates a SceneDesc with a custom filterShader that uses word0/word1 as groups shapes can belong to, word2 as a mask on word0, and word3 as a mask on word1.
 	/// </summary>
 	/// <param name="CPxTolerancesScale"></param>
 	/// <returns></returns>
 	CPxAPI CSTRUCT CPxSceneDesc* NewCPxSceneDesc(CSTRUCT CPxTolerancesScale);
 	CPxAPI void CPxSceneDesc_set_gravity(CSTRUCT CPxSceneDesc*, CSTRUCT CPxVec3);
 	CPxAPI void CPxSceneDesc_set_cpuDispatcher(CSTRUCT CPxSceneDesc*, CSTRUCT CPxCpuDispatcher*);
+	CPxAPI void CPxSceneDesc_set_onContactCallback(CSTRUCT CPxSceneDesc*, CPxonContactCallback cb);
 	CPxAPI void FreeCPxSceneDesc(CSTRUCT CPxSceneDesc*);
 
 #ifdef __cplusplus