diff --git a/EventRecord/Event.h b/EventRecord/Event.h
--- a/EventRecord/Event.h
+++ b/EventRecord/Event.h
@@ -1,474 +1,512 @@
 // -*- C++ -*-
 //
 // Event.h is a part of ThePEG - Toolkit for HEP Event Generation
 // Copyright (C) 1999-2019 Leif Lonnblad
 //
 // ThePEG is licenced under version 3 of the GPL, see COPYING for details.
 // Please respect the MCnet academic guidelines, see GUIDELINES for details.
 //
 #ifndef ThePEG_Event_H
 #define ThePEG_Event_H
 // This is the decalaration of the Event class.
 
 #include "Particle.h"
 #include "StandardSelectors.h"
 #include "SubProcess.h"
 #include "ThePEG/Utilities/Named.h"
+#include "ThePEG/Utilities/AnyReference.h"
 
 namespace ThePEG {
 
 /**
  * The Event class contains all Particles produced in the generation
  * of an event. The particles are divided into Collisions
  * corresponding to the actiual collisions between incoming particles
  * in a bunch crossing.
  *
  * Event inherits from the Named which holds the name of an event.
  *
  * @see Collision
  * @see Step
  * @see SubProcess
  * @see Particle
  * @see SelectorBase
  * @see Named
  *
  */
 class Event : public EventRecordBase, public Named {
 
 public:
 
   /**
    * EventHandler is a friend of most Event classes.
    */
   friend class EventHandler;
   /** Most of the Event classes are friends with each other. */
   friend class Collision;
 
   /** Map colour lines to indices. */
   typedef map<tcColinePtr, int> ColourLineMap;
 
 public:
 
   /**
    * The standard constructor for an Event takes as arguments a pair
    * of colliding particles (corresponding to the primary collision in
    * case of multiple collisions in an event). Optionally a pointer to
    * the EventHandler which performed the generation, an event name
    * and event number can be given.
    * @param newIncoming a pair of incoming particles to the prinary Collision.
    * @param newHandler the handler object in charge of the generation
    * of this Event.
    * @param newName the name of this event.
    * @param newNumber the number of this event.
    * @param weight the weight of this event
    */
   Event(const PPair & newIncoming, tcEventBasePtr newHandler = tcEventBasePtr(),
 	string newName = "", long newNumber = -1, double weight = 1.0);
 
   /**
    * The copy constructor.
    */
   Event(const Event&);
 
   /**
    * The destructor.
    */
   ~Event();
 
   /**
    * Returns a full clone of this Event. All collisions,
    * <code>Particle</code>s etc. in this Event are cloned.
    */
   EventPtr clone() const;
 
 public:
 
   /**
    * Return a pointer to the EventHandler which produced this
    * Event. May be the null pointer.
    */
   tcEventBasePtr handler() const { return theHandler; }
 
   /** @name Functions for accessing particles etc. */
   //@{
   /**
    * Extract particles from this event which satisfies the
    * requirements given by an object of the SelectorBase class.
    * @param r an output iterator specifying where the extracted
    * (pointers to) particles will be appended.
    * @param s SelectorBase object defining which particles should be
    * extracted.
     */
   template <class OutputIterator>
   void select(OutputIterator r, const SelectorBase & s) const;
 
   /**
    * Extract all final state particles in this Event.
    * @param r an output iterator specifying where the extracted
    * (pointers to) particles will be appended.
    */
   template <class OutputIterator>
   void selectFinalState(OutputIterator r) const {
     select(r, SelectFinalState());
   }
 
   /**
    * Extract all final state particles in this Event.
    * @param c a container where the extracted (pointers to) particles
    * will be appended.
    */
   template <class Container>
   void getFinalState(Container & c) const {
     selectFinalState(inserter(c));
   }
 
   /**
    * Extract all final state particles in this Event.
    * @return a vector of pointers to the extracted particles.
    */
   tPVector getFinalState() const {
     tPVector ret;
     selectFinalState(back_inserter(ret));
     return ret;
   }
 
   /**
    * Return a pointer to the primary Collision in this Event. May
    * be the null pointer.
    */
   tCollPtr primaryCollision() const {
     return collisions().empty() ? tCollPtr() : tCollPtr(collisions()[0]);
   }
 
   /**
    * Return a possibly empty list of collisions in this Event.
    */
   const CollisionVector & collisions() const { return theCollisions; }
 
   /**
    * Return a pointer to the primary SubProcess in the prinmary
    * Collision in this Event. May be the null pointer.
    */
   tSubProPtr primarySubProcess() const;
 
   /**
    * Return a reference to the pair of colliding particles in the
    * primary Collision of this Event.
    */
   const PPair & incoming() const { return theIncoming; }
 
   //@}
 
   /**
    * Create a new Collision in this event and return a pointer to it.
    */
   tCollPtr newCollision();
 
   /**
    * Create a new Step in the current Collision, which is a copy of
    * the last Step (if any) and return a pointer to it. If no
    * collision exists, one will be added.
    */
   tStepPtr newStep();
 
   /**
    * Transform all particles in this Event.
    */
   void transform(const LorentzRotation &);
 
   /**
    * Return the number assigned to this Event. The name is accessed
    * with the name() method of the Named base class.
    */
   long number() const { return theNumber; }
 
   /**
    * Return the index of the given colour line.
    */
   int colourLineIndex(tcColinePtr) const;
 
   /** @name Functions for removing entires from an Event. */
   //@{
   /**
    * Remove (recursively) the decay products from a given Particle and
    * add the particle to the list of final state particles.
    */
   void removeDecay(tPPtr);
 
   /**
    * Remove the given Particle from the Collision. If this was the
    * last daughter of the mother Particle, the latter is added to the
    * list of final state particles.
    */
   void removeParticle(tPPtr);
 
   /**
    * Remove all steps which have no new particles introduced in them.
    */
   void cleanSteps();
 
   //@}
 
   /**
    * Return the weight associated with this event.
    */
   double weight() const { return theWeight; }
 
   /**
    * Return an optional named weight associated to this event. Returns
    * 0, if no weight identified by this name is present.
    */
   double optionalWeight(const string& name) const;
 
   /**
    * Return the optional named weights associated to this event.
    */
   const map<string,double>& optionalWeights() const { return theOptionalWeights; }
 
   /**
    * Print this Event in Graphviz format on the standard output.
    */
   void printGraphviz() const;
 
   /**
    * Set the weight associated with this event.
    */
   void weight(double w) { theWeight = w; }
 
   /**
    * Set an optional named weight associated to this event.
    */
   void optionalWeight(const string& name, double value);
 
   /**
    * Access the optional named weights associated to this event.
    */
   map<string,double>& optionalWeights() { return theOptionalWeights; }
 
   /**
    * Set event info.
    */
   void setInfo(tcEventBasePtr newHandler, string newName,
 	       long newNumber, double weight);
 
   /**
    * Add a collision to this Event.
    */
   void addCollision(tCollPtr c);
 
   /**
    * Set the primary collision in this Event.
    */
   void primaryCollision(tCollPtr c);
 
+public:
+
+  /**
+   * Check for meta information
+   */
+  bool hasMeta(const string& id) const {
+    return theMeta.find(id) != theMeta.end();
+  }
+
+  /**
+   * Set meta information.
+   */
+  template<class T>
+  void meta(const string& id, T& ref) {
+    theMeta[id] = AnyReference(ref);
+  }
+
+  /**
+   * Erase meta information.
+   */
+  void eraseMeta(const string& id) {
+    theMeta.erase(id);
+  }
+
+  /**
+   * Retrieve meta information.
+   */
+  template<class T>
+  T& meta(const string& id) const {
+    return theMeta.find(id)->second.cast<T>();
+  }
+
 protected:
 
   /**
    * Add a range of particles to this Collision.
    */
   template <class Iterator>
   void addParticles(Iterator first, Iterator last) {
     while ( first != last ) addParticle(*first++);
   }
 
   /**
    * Add a particle to this Collision.
    */
   void addParticle(tPPtr p);
 
   /**
    * Add a new SubProcess to this Event. For book keeping purposes
    * only. The sub-processes are accessed from the different
    * Collisions in this Event.
    */
   void addSubProcess(tSubProPtr p) {
     if ( p ) allSubProcesses.insert(p);
   }
 
   /**
    * Remove a SubProcess from this Event.
    */
   void removeSubProcess(tSubProPtr p) { allSubProcesses.erase(p); }
 
   /**
    * Add a new Step to this Collision. For book keeping purposes
    * only. The steps are accessed from the different Collisions in
    * this Event.
    */
   void addStep(tStepPtr s) { 
     if ( s ) allSteps.insert(s); 
   }
 
   /**
    * Remove a given Particle entry.
    */
   void removeEntry(tPPtr p);
 
   /**
    * Rebind to cloned objects. When an Event is cloned, a shallow
    * copy is done first, then all <code>Particle</code>s etc, are
    * cloned, and finally this method is used to see to that the
    * pointers in the cloned Event points to the cloned
    * <code>Particle</code>s etc.
    */
   void rebind(const EventTranslationMap & trans);
 
 public:
 
   /**
    * Standard function for writing to a persistent stream.
    */
   void persistentOutput(PersistentOStream &) const;
 
   /**
    * Standard functions for reading from a persistent stream.
    */
   void persistentInput(PersistentIStream &, int);
 
   /**
    * Standard Init function. @see Base::Init().
    */
   static void Init();
 
 private:
 
   /**
    * The pair of colliding particles.
    */
   PPair theIncoming;
 
   /**
    * A vector of collisions in this Event.
    */
   CollisionVector theCollisions;
 
   /**
    * A set of all particles in this Event.
    */
   StepSet allSteps;
 
   /**
    * A set of all sub-processes in this Event.
    */
   SubProcessSet allSubProcesses;
 
   /**
    * A set of all particles in this Event.
    */
   ParticleSet allParticles;
 
   /**
    * A pointer to the EventHandler which performed the generation
    * of this Event.
    */
   tcEventBasePtr theHandler;
 
   /**
    * Map of all registered colour lines to their index numbers.
    */
   mutable ColourLineMap theColourLines;
 
   /**
    * The number assigned to this Event.
    */
   long theNumber;
 
   /**
    * The weight associated with this event.
    */
   double theWeight;
 
   /**
    * Optional named weights
    */
   map<string,double> theOptionalWeights;
 
   /**
    * Counter to keep track of particle numbering.
    */
   long theParticleNumber;
 
+  /**
+   * The meta information
+   */
+  map<string,AnyReference> theMeta;
+
 public:
 
   /**
    * Print out debugging information for this object on std::cerr. To
    * be called from within a debugger via the debug() function.
    */
   virtual void debugme() const;
 
 private:
 
   /**
    * Describe concrete class with persistent data.
    */
   static ClassDescription<Event> initEvent;
 
   /**
    * Private default constructor must only be used by the
    * PersistentIStream class via the ClassTraits<Event> class .
    */
   Event() : theNumber(-1), theWeight(1.0), theParticleNumber(0) {}
 
   /**
    * The ClassTraits<Event> class must be a friend to be able to
    * use the private default constructor.
    */
   friend struct ClassTraits<Event>;
 
   /**
    * The assignment operator is private and not implemented.
    */
   Event & operator=(const Event&) = delete;
 
 };
 
 /** Output a Event to a standard ostream. */
 ostream & operator<<(ostream &, const Event &);
 
 /** Print event tree in Graphviz format, ready for plotting. */
 void printGraphviz(ostream &, tcEventPtr);
 
 /** @cond TRAITSPECIALIZATIONS */
 
 /** This template specialization informs ThePEG about the
  *  base class of Event. */
 template <>
 struct BaseClassTrait<Event,1>: public ClassTraitsType {
   /** Typedef of the first base class of Collision. */
   typedef EventRecordBase NthBase;
 };
 
 /** This template specialization informs ThePEG about the name of
  *  the Event class and how to create it. */
 template <>
 struct ClassTraits<Event>: public ClassTraitsBase<Event> {
   /** Return a platform-independent class name */
   static string className() { return "ThePEG::Event"; }
   /** Create a Event object. */
   static TPtr create() { return TPtr::Create(Event()); }
 };
 
 /** @endcond */
 
 }
 
 #include "Collision.h"
 
 inline ThePEG::tSubProPtr ThePEG::Event::primarySubProcess() const {
   return collisions().empty() ? ThePEG::tSubProPtr() :
     ThePEG::tSubProPtr(primaryCollision()->primarySubProcess());
 }
 
 namespace ThePEG {
   template <class OutputIterator>
   void Event::select(OutputIterator r, const SelectorBase & s) const {
     if ( s.allCollisions() ) {
       for ( CollisionVector::const_iterator it = theCollisions.begin();
 	    it != theCollisions.end(); ++it ) (**it).select(r, s);
     } else {
       primaryCollision()->select(r, s);
     }
   }
 }
 
 #endif /* ThePEG_Event_H */