diff --git a/Simulation/ISF/ISF_Geant4/ISF_Geant4Interfaces/ISF_Geant4Interfaces/ITransportTool.h b/Simulation/ISF/ISF_Geant4/ISF_Geant4Interfaces/ISF_Geant4Interfaces/ITransportTool.h
index 4a927615e5afeac201aeefc17b50c8e5d710b2f6..60af27e8d06c9b043bd2baa0ef8da5f9c3fdd548 100644
--- a/Simulation/ISF/ISF_Geant4/ISF_Geant4Interfaces/ISF_Geant4Interfaces/ITransportTool.h
+++ b/Simulation/ISF/ISF_Geant4/ISF_Geant4Interfaces/ISF_Geant4Interfaces/ITransportTool.h
@@ -47,10 +47,10 @@ namespace iGeant4 {
        static const InterfaceID& interfaceID() { return IID_ITransportTool; }
 
        /** Processes ISF particle */
-       virtual StatusCode process(const ISF::ISFParticle& isp) const = 0;
+       virtual StatusCode process(const ISF::ISFParticle& isp) = 0;
 
        /** Processes vector of ISF particles */
-       virtual StatusCode processVector(const std::vector<const ISF::ISFParticle*>& particles) const = 0;
+       virtual StatusCode processVector(const std::vector<const ISF::ISFParticle*>& ispVector) = 0;
   };
 
 } // end of namespace