diff --git a/lib/qcd/hmc/GenericHMCrunner.h b/lib/qcd/hmc/GenericHMCrunner.h
index 5bfe7a90..de9b36d3 100644
--- a/lib/qcd/hmc/GenericHMCrunner.h
+++ b/lib/qcd/hmc/GenericHMCrunner.h
@@ -52,26 +52,10 @@ class HMCWrapperTemplate: public HMCBase {
   template <typename S = NoSmearing<Implementation> >
   using IntegratorType = Integrator<Implementation, S, RepresentationsPolicy>;
 
-  enum StartType_t {
-    ColdStart,
-    HotStart,
-    TepidStart,
-    CheckpointStart,
-    FilenameStart
-  };
-
-  struct HMCPayload {
-    StartType_t StartType;
-    HMCparameters Parameters;
-
-    HMCPayload() { StartType = HotStart; }
-  };
-
-  // These can be rationalised, some private
-  HMCPayload Payload;  // Parameters
+  HMCparameters Parameters;
   HMCResourceManager<Implementation> Resources;
-  IntegratorParameters MDparameters;
 
+  // The set of actions
   ActionSet<Field, RepresentationsPolicy> TheAction;
 
   // A vector of HmcObservable that can be injected from outside
@@ -80,44 +64,39 @@ class HMCWrapperTemplate: public HMCBase {
   void ReadCommandLine(int argc, char **argv) {
     std::string arg;
 
-    if (GridCmdOptionExists(argv, argv + argc, "--StartType")) {
-      arg = GridCmdOptionPayload(argv, argv + argc, "--StartType");
-      if (arg == "HotStart") {
-        Payload.StartType = HotStart;
-      } else if (arg == "ColdStart") {
-        Payload.StartType = ColdStart;
-      } else if (arg == "TepidStart") {
-        Payload.StartType = TepidStart;
-      } else if (arg == "CheckpointStart") {
-        Payload.StartType = CheckpointStart;
-      } else {
-        std::cout << GridLogError << "Unrecognized option in --StartType\n";
+    if (GridCmdOptionExists(argv, argv + argc, "--StartingType")) {
+      arg = GridCmdOptionPayload(argv, argv + argc, "--StartingType");
+
+      if (arg != "HotStart" && arg != "ColdStart" && arg != "TepidStart" &&
+          arg != "CheckpointStart") {
+        std::cout << GridLogError << "Unrecognized option in --StartingType\n";
         std::cout
             << GridLogError
             << "Valid [HotStart, ColdStart, TepidStart, CheckpointStart]\n";
-        assert(0);
+        exit(1);
       }
+      Parameters.StartingType = arg;
     }
 
     if (GridCmdOptionExists(argv, argv + argc, "--StartTrajectory")) {
       arg = GridCmdOptionPayload(argv, argv + argc, "--StartTrajectory");
       std::vector<int> ivec(0);
       GridCmdOptionIntVector(arg, ivec);
-      Payload.Parameters.StartTrajectory = ivec[0];
+      Parameters.StartTrajectory = ivec[0];
     }
 
     if (GridCmdOptionExists(argv, argv + argc, "--Trajectories")) {
       arg = GridCmdOptionPayload(argv, argv + argc, "--Trajectories");
       std::vector<int> ivec(0);
       GridCmdOptionIntVector(arg, ivec);
-      Payload.Parameters.Trajectories = ivec[0];
+      Parameters.Trajectories = ivec[0];
     }
 
     if (GridCmdOptionExists(argv, argv + argc, "--Thermalizations")) {
       arg = GridCmdOptionPayload(argv, argv + argc, "--Thermalizations");
       std::vector<int> ivec(0);
       GridCmdOptionIntVector(arg, ivec);
-      Payload.Parameters.NoMetropolisUntil = ivec[0];
+      Parameters.NoMetropolisUntil = ivec[0];
     }
   }
 
@@ -143,30 +122,30 @@ class HMCWrapperTemplate: public HMCBase {
 
     // Can move this outside?
     typedef IntegratorType<SmearingPolicy> TheIntegrator;
-    TheIntegrator MDynamics(UGrid, MDparameters, TheAction, Smearing);
+    TheIntegrator MDynamics(UGrid, Parameters.MD, TheAction, Smearing);
 
-    if (Payload.StartType == HotStart) {
+    if (Parameters.StartingType == "HotStart") {
       // Hot start
       Resources.SeedFixedIntegers();
       Implementation::HotConfiguration(Resources.GetParallelRNG(), U);
-    } else if (Payload.StartType == ColdStart) {
+    } else if (Parameters.StartingType == "ColdStart") {
       // Cold start
       Resources.SeedFixedIntegers();
       Implementation::ColdConfiguration(Resources.GetParallelRNG(), U);
-    } else if (Payload.StartType == TepidStart) {
+    } else if (Parameters.StartingType == "TepidStart") {
       // Tepid start
       Resources.SeedFixedIntegers();
       Implementation::TepidConfiguration(Resources.GetParallelRNG(), U);
-    } else if (Payload.StartType == CheckpointStart) {
+    } else if (Parameters.StartingType == "CheckpointStart") {
       // CheckpointRestart
-      Resources.GetCheckPointer()->CheckpointRestore(Payload.Parameters.StartTrajectory, U,
+      Resources.GetCheckPointer()->CheckpointRestore(Parameters.StartTrajectory, U,
                                    Resources.GetSerialRNG(),
                                    Resources.GetParallelRNG());
     }
 
     Smearing.set_Field(U);
 
-    HybridMonteCarlo<TheIntegrator> HMC(Payload.Parameters, MDynamics,
+    HybridMonteCarlo<TheIntegrator> HMC(Parameters, MDynamics,
                                         Resources.GetSerialRNG(),
                                         Resources.GetParallelRNG(), U);
 
diff --git a/lib/qcd/hmc/HMC.h b/lib/qcd/hmc/HMC.h
index c5e9e65b..3304ad4f 100644
--- a/lib/qcd/hmc/HMC.h
+++ b/lib/qcd/hmc/HMC.h
@@ -50,24 +50,39 @@ struct HMCparameters: Serializable {
   Integer, Trajectories, /* @brief Number of sweeps in this run */
   bool, MetropolisTest,
   Integer, NoMetropolisUntil,
+  std::string, StartingType,
+  IntegratorParameters, MD,
   )
 
-  // nest here the MDparameters and make all serializable
-
   HMCparameters() {
     ////////////////////////////// Default values
     MetropolisTest    = true;
     NoMetropolisUntil = 10;
     StartTrajectory   = 0;
     Trajectories      = 10;
+    StartingType      = "HotStart";
     /////////////////////////////////
   }
 
+  template <class ReaderClass >
+  HMCparameters(Reader<ReaderClass> & TheReader){
+  	initialize(TheReader);
+  }
+
+  template < class ReaderClass > 
+  void initialize(Reader<ReaderClass> &TheReader){
+  	std::cout << "Reading HMC\n";
+  	read(TheReader, "HMC", *this);
+  }
+
+
   void print_parameters() const {
     std::cout << GridLogMessage << "[HMC parameters] Trajectories            : " << Trajectories << "\n";
     std::cout << GridLogMessage << "[HMC parameters] Start trajectory        : " << StartTrajectory << "\n";
     std::cout << GridLogMessage << "[HMC parameters] Metropolis test (on/off): " << std::boolalpha << MetropolisTest << "\n";
     std::cout << GridLogMessage << "[HMC parameters] Thermalization trajs    : " << NoMetropolisUntil << "\n";
+    std::cout << GridLogMessage << "[HMC parameters] Starting type           : " << StartingType << "\n";
+    MD.print_parameters();
   }
   
 };
@@ -209,7 +224,6 @@ class HybridMonteCarlo {
     Field Ucopy(Ucur._grid);
 
     Params.print_parameters();
-    TheIntegrator.print_parameters();
     TheIntegrator.print_actions();
 
     // Actual updates (evolve a copy Ucopy then copy back eventually)
diff --git a/lib/qcd/hmc/integrators/Integrator.h b/lib/qcd/hmc/integrators/Integrator.h
index 6101e225..6a72919e 100644
--- a/lib/qcd/hmc/integrators/Integrator.h
+++ b/lib/qcd/hmc/integrators/Integrator.h
@@ -54,10 +54,12 @@ public:
 
   template <class ReaderClass, typename std::enable_if<isReader<ReaderClass>::value, int >::type = 0 >
   IntegratorParameters(ReaderClass & Reader){
+    std::cout << "Reading integrator\n";
   	read(Reader, "Integrator", *this);
   }
 
-  void print_parameters() {
+  void print_parameters() const {
+    std::cout << GridLogMessage << "[Integrator] Type               : " << name << std::endl;
     std::cout << GridLogMessage << "[Integrator] Trajectory length  : " << trajL << std::endl;
     std::cout << GridLogMessage << "[Integrator] Number of MD steps : " << MDsteps << std::endl;
     std::cout << GridLogMessage << "[Integrator] Step size          : " << trajL/MDsteps << std::endl;
diff --git a/tests/hmc/Test_hmc_Factories.cc b/tests/hmc/Test_hmc_Factories.cc
index f33beeb1..841d009d 100644
--- a/tests/hmc/Test_hmc_Factories.cc
+++ b/tests/hmc/Test_hmc_Factories.cc
@@ -43,11 +43,12 @@ int main(int argc, char **argv) {
   typedef GenericHMCRunner<MinimumNorm2> HMCWrapper;  // Uses the default minimum norm
   typedef Grid::XmlReader InputFileReader; 
 
-  // Reader
+  // Reader, file should come from command line
   InputFileReader Reader("input.wilson_gauge.params.xml");
 
   HMCWrapper TheHMC;
 
+  TheHMC.Parameters.initialize(Reader);
   TheHMC.Resources.initialize(Reader);
 
   // Construct observables
@@ -67,20 +68,13 @@ int main(int argc, char **argv) {
 
   ActionLevel<HMCWrapper::Field> Level1(1);
   Level1.push_back(&Waction);
-  //Level1.push_back(WGMod.getPtr());
   TheHMC.TheAction.push_back(Level1);
   /////////////////////////////////////////////////////////////
 
-  // Nest MDparameters in the HMCparameters->HMCPayload
-  // make it serializable 
-  TheHMC.MDparameters.MDsteps = 20;
-  TheHMC.MDparameters.trajL = 1.0;
-
   // eventually smearing here
   // ...
   ////////////////////////////////////////////////////////////////
 
-  TheHMC.ReadCommandLine(argc, argv); // these must be parameters from file
   TheHMC.Run();  // no smearing
 
   Grid_finalize();
diff --git a/tests/hmc/Test_hmc_WilsonGauge_Binary.cc b/tests/hmc/Test_hmc_WilsonGauge_Binary.cc
index 9c809e8b..c1e67c0b 100644
--- a/tests/hmc/Test_hmc_WilsonGauge_Binary.cc
+++ b/tests/hmc/Test_hmc_WilsonGauge_Binary.cc
@@ -83,10 +83,9 @@ int main(int argc, char **argv) {
   TheHMC.TheAction.push_back(Level1);
   /////////////////////////////////////////////////////////////
 
-  // Nest MDparameters in the HMCparameters->HMCPayload
-  // make it serializable 
-  TheHMC.MDparameters.MDsteps = 20;
-  TheHMC.MDparameters.trajL = 1.0;
+  // HMC parameters are serialisable 
+  TheHMC.Parameters.MD.MDsteps = 20;
+  TheHMC.Parameters.MD.trajL   = 1.0;
 
   TheHMC.ReadCommandLine(argc, argv); // these must be parameters from file
   TheHMC.Run();  // no smearing