diff --git a/SimG4CMS/Muon/interface/MuonMe0FrameRotation.h b/SimG4CMS/Muon/interface/MuonMe0FrameRotation.h
new file mode 100644
index 0000000000000..1a6aa27d07fc6
--- /dev/null
+++ b/SimG4CMS/Muon/interface/MuonMe0FrameRotation.h
@@ -0,0 +1,34 @@
+#ifndef MuonMe0FrameRotation_H
+#define MuonMe0FrameRotation_H
+
+/** \class MuonMe0FrameRotation
+ *
+ * implementation of FrameRotation for the muon ME0
+ * 
+ * \author Arno Straessner, CERN <arno.straessner@cern.ch>
+ *
+ * Modification:
+ *
+ */
+
+#include "SimG4CMS/Muon/interface/MuonFrameRotation.h"
+#include "SimG4CMS/Muon/interface/MuonG4Numbering.h"
+
+#include "G4Step.hh"
+
+class DDCompactView;
+
+class MuonMe0FrameRotation : public MuonFrameRotation {
+
+public:
+  MuonMe0FrameRotation( const DDCompactView& cpv );
+  virtual ~MuonMe0FrameRotation();
+  virtual Local3DPoint transformPoint(const Local3DPoint &, const G4Step *) const;
+
+private:
+  MuonG4Numbering* g4numbering;
+  int              theSectorLevel;
+};
+
+
+#endif
diff --git a/SimG4CMS/Muon/interface/MuonSlaveSD.h b/SimG4CMS/Muon/interface/MuonSlaveSD.h
index 387d5ac62d154..cae393fb8780b 100644
--- a/SimG4CMS/Muon/interface/MuonSlaveSD.h
+++ b/SimG4CMS/Muon/interface/MuonSlaveSD.h
@@ -65,4 +65,16 @@ class FormatRpcHits {
   int sortId (const PSimHit & a)  const;
 };
 
+class FormatGemHits {
+ public:
+  bool operator() (const PSimHit & a, const PSimHit & b);
+  int sortId (const PSimHit & a)  const;
+};
+
+class FormatMe0Hits {
+ public:
+  bool operator() (const PSimHit & a, const PSimHit & b);
+  int sortId (const PSimHit & a)  const;
+};
+
 #endif // MuonSlaveSD_h
diff --git a/SimG4CMS/Muon/src/MuonGemFrameRotation.cc b/SimG4CMS/Muon/src/MuonGemFrameRotation.cc
index fbe60a5c8b0f9..406417bda5945 100644
--- a/SimG4CMS/Muon/src/MuonGemFrameRotation.cc
+++ b/SimG4CMS/Muon/src/MuonGemFrameRotation.cc
@@ -36,7 +36,8 @@ Local3DPoint MuonGemFrameRotation::transformPoint(const Local3DPoint & point,con
 	    << " Rotation " << rotated << std::endl;
 #endif
   if (rotated) {
-    return Local3DPoint(-point.x(),point.z(),point.y());
+    //    return Local3DPoint(-point.x(),point.z(),point.y());
+    return Local3DPoint(point.x(),point.z(),-point.y());
   } else {
     return Local3DPoint(point.x(),point.z(),-point.y());
   }
diff --git a/SimG4CMS/Muon/src/MuonMe0FrameRotation.cc b/SimG4CMS/Muon/src/MuonMe0FrameRotation.cc
new file mode 100644
index 0000000000000..d604a30417cf5
--- /dev/null
+++ b/SimG4CMS/Muon/src/MuonMe0FrameRotation.cc
@@ -0,0 +1,44 @@
+#include "SimG4CMS/Muon/interface/MuonMe0FrameRotation.h"
+#include "Geometry/MuonNumbering/interface/MuonDDDConstants.h"
+#include "Geometry/MuonNumbering/interface/MuonBaseNumber.h"
+
+#include "G4StepPoint.hh"
+#include "G4TouchableHistory.hh"
+
+//#define LOCAL_DEBUG
+
+MuonMe0FrameRotation::MuonMe0FrameRotation(const DDCompactView& cpv) : MuonFrameRotation::MuonFrameRotation(cpv) {
+  g4numbering     = new MuonG4Numbering(cpv);
+  MuonDDDConstants muonConstants(cpv);
+  int theLevelPart= muonConstants.getValue("level");
+  theSectorLevel  = muonConstants.getValue("mg_sector")/theLevelPart;
+#ifdef LOCAL_DEBUG
+  std::cout << "MuonMe0FrameRotation: theSectorLevel " << theSectorLevel 
+	    << std::endl;
+#endif
+}
+
+MuonMe0FrameRotation::~MuonMe0FrameRotation() {
+  delete g4numbering;
+}
+
+Local3DPoint MuonMe0FrameRotation::transformPoint(const Local3DPoint & point,const G4Step * aStep=0) const {
+  if (!aStep) return Local3DPoint(0.,0.,0.);  
+
+  //check if it is rotated
+#ifdef LOCAL_DEBUG
+  std::cout << "Position " << aStep->GetPreStepPoint()->GetPosition() << std::endl;
+#endif
+  MuonBaseNumber num = g4numbering->PhysicalVolumeToBaseNumber(aStep);
+  bool rotated       = (num.getBaseNo(theSectorLevel)>=50);
+#ifdef LOCAL_DEBUG
+  std::cout << "MuonMe0FrameRotation num " << num.getBaseNo(theSectorLevel)
+	    << " Rotation " << rotated << std::endl;
+#endif
+  if (rotated) {
+    //    return Local3DPoint(-point.x(),point.z(),point.y());
+    return Local3DPoint(point.x(),point.z(),-point.y());
+  } else {
+    return Local3DPoint(point.x(),point.z(),-point.y());
+  }
+}
diff --git a/SimG4CMS/Muon/src/MuonSensitiveDetector.cc b/SimG4CMS/Muon/src/MuonSensitiveDetector.cc
index 3da99ded5c2d5..b6e1369064411 100644
--- a/SimG4CMS/Muon/src/MuonSensitiveDetector.cc
+++ b/SimG4CMS/Muon/src/MuonSensitiveDetector.cc
@@ -1,8 +1,9 @@
 #include "SimG4CMS/Muon/interface/MuonSensitiveDetector.h"
 #include "SimG4CMS/Muon/interface/MuonSlaveSD.h"
 #include "SimG4CMS/Muon//interface/MuonEndcapFrameRotation.h"
-#include "SimG4CMS/Muon/interface/MuonGemFrameRotation.h"
 #include "SimG4CMS/Muon/interface/MuonRpcFrameRotation.h"
+#include "SimG4CMS/Muon/interface/MuonGemFrameRotation.h"
+#include "SimG4CMS/Muon/interface/MuonMe0FrameRotation.h"
 #include "Geometry/MuonNumbering/interface/MuonSubDetector.h"
 
 #include "DataFormats/GeometryVector/interface/LocalVector.h"
@@ -59,6 +60,9 @@ MuonSensitiveDetector::MuonSensitiveDetector(std::string name,
   } else if (detector->isGem()) {
     //    cout << "MuonFrameRotation create MuonGemFrameRotation"<<endl;
     theRotation=new MuonGemFrameRotation( cpv );
+  } else if (detector->isME0()) {
+    //    cout << "MuonFrameRotation create MuonMe0FrameRotation"<<endl;
+    theRotation=new MuonMe0FrameRotation( cpv );
   }  else {
     theRotation = 0;
   }
diff --git a/SimG4CMS/Muon/src/MuonSlaveSD.cc b/SimG4CMS/Muon/src/MuonSlaveSD.cc
index 793e69d6f6d7c..71cedab289522 100644
--- a/SimG4CMS/Muon/src/MuonSlaveSD.cc
+++ b/SimG4CMS/Muon/src/MuonSlaveSD.cc
@@ -33,8 +33,11 @@ bool MuonSlaveSD::format()
     sort(hits_.begin(),hits_.end(), FormatEndcapHits());
   } else if (detector->isRpc()) {
     sort(hits_.begin(),hits_.end(), FormatRpcHits());
+  } else if (detector->isGem()) {
+    sort(hits_.begin(),hits_.end(), FormatGemHits());
+  } else if (detector->isME0()) {
+    sort(hits_.begin(),hits_.end(), FormatMe0Hits());
   } 
-  
   return true;
 }
 
@@ -69,3 +72,23 @@ int FormatRpcHits::sortId(const PSimHit & a)  const
   return a.detUnitId();
 }
 
+bool FormatGemHits::operator() (const PSimHit & a, const PSimHit & b)
+{
+  return (sortId(a)<sortId(b));
+}
+
+int FormatGemHits::sortId(const PSimHit & a)  const 
+{
+  return a.detUnitId();
+}
+
+
+bool FormatMe0Hits::operator() (const PSimHit & a, const PSimHit & b)
+{
+  return (sortId(a)<sortId(b));
+}
+
+int FormatMe0Hits::sortId(const PSimHit & a)  const 
+{
+  return a.detUnitId();
+}