diff --git a/cpp/VSLAMGraph.cpp b/cpp/VSLAMGraph.cpp
index 830650c22..d09a1ff44 100644
--- a/cpp/VSLAMGraph.cpp
+++ b/cpp/VSLAMGraph.cpp
@@ -78,6 +78,13 @@ VSLAMGraph::VSLAMGraph(const std::string& path)
   ifs.close();
 }
 
+/* ************************************************************************* */
+bool VSLAMGraph::equals(const VSLAMGraph& p, double tol) const {
+  if (&p == NULL) return false;
+  if (nFrames != p.nFrames || feat_ids != p.feat_ids ) return false;
+  return true;
+}
+
 /* ************************************************************************* */
 bool compareLandmark(const std::string& key,
 					const VSLAMConfig& feasible,
diff --git a/cpp/VSLAMGraph.h b/cpp/VSLAMGraph.h
index dd116072f..8e97eec36 100644
--- a/cpp/VSLAMGraph.h
+++ b/cpp/VSLAMGraph.h
@@ -16,13 +16,14 @@
 #include "FactorGraph-inl.h"
 #include "VSLAMFactor.h"
 #include "VSLAMConfig.h"
+#include "Testable.h"
 
 namespace gtsam{
 
 /**
  * Non-linear factor graph for visual SLAM
  */
-class VSLAMGraph : public gtsam::NonlinearFactorGraph<VSLAMConfig>{
+class VSLAMGraph : public gtsam::NonlinearFactorGraph<VSLAMConfig>, Testable<VSLAMGraph>{
 private:
 	int nFrames;
 	typedef map <int, int> feat_ids_type;
@@ -46,6 +47,11 @@ public:
     gtsam::NonlinearFactorGraph<VSLAMConfig>::print(s);
   }
 
+  /**
+   * equals
+   */
+  bool equals(const VSLAMGraph&, double tol=1e-9) const;
+
   // Getters
   int Get_nFrames(){return nFrames;};
   int Get_nFeat_ids(){return feat_ids.size();};
@@ -57,6 +63,15 @@ public:
    *  @param p to which point to constrain it to
    */
   void addLandmarkConstraint(int j, const Point3& p = Point3());
+
+private:
+	/** Serialization function */
+	friend class boost::serialization::access;
+	template<class Archive>
+	void serialize(Archive & ar, const unsigned int version) {
+		ar & BOOST_SERIALIZATION_NVP(nFrames);
+		ar & BOOST_SERIALIZATION_NVP(feat_ids);
+	}
 };
 
 } // namespace gtsam