diff --git a/apf/apfAggregateNumbering.cc b/apf/apfAggregateNumbering.cc
index 4e77a9578..17099d815 100644
--- a/apf/apfAggregateNumbering.cc
+++ b/apf/apfAggregateNumbering.cc
@@ -1,4 +1,5 @@
 #include "apfAggregateNumbering.h"
+#include "apfAggregateNumberingClass.h"
 #include "apfField.h"
 #include "apfNumberingClass.h"
 #include "apfTagData.h"
@@ -8,51 +9,9 @@
 #include <set>
 namespace apf
 {
-  template <class T>
-  class AggregateNumberingOf : public NumberingOf<T>
-  {
-  public:
-    AggregateNumberingOf()
-      : NumberingOf<T>()
-      , nd_ids(NULL)
-      , shr(NULL)
-      , blks_per_nd(0)
-      , dofs_per_blk(0)
-      , slf(-1)
-      , strds()
-      , frsts()
-      , lcl_strd(0)
-    { }
-    void init(const char * n,
-              Mesh * m,
-              Sharing * sh,
-              FieldShape * s,
-              int blks,
-              int bs);
-    void init(Field * f, Sharing * sh, int blks, int bs);
-    void globalize();
-    virtual void getAll(MeshEntity * e, T * dat);
-    virtual T get(MeshEntity * e, int nd, int cmp);
-    virtual void set(MeshEntity*,int,int,T) {}
-    Sharing * getSharing() const { return shr; }
-    void setSharing(Sharing * s) { shr = s; }
-    int countBlocks() const { return blks_per_nd; }
-    int blockSize() const { return dofs_per_blk; }
-    T getLocalStride() const { return lcl_strd; }
-    T getScopeStride() const { return strds[slf]; }
-    T getLocalFirstDof() const { return frsts[slf]; }
-    T getStride(int peer) const { return strds[peer]; };
-    T getFirstDof(int peer) const { return frsts[peer]; }
-  private:
-    FieldDataOf<T> * nd_ids;
-    Sharing * shr;
-    int blks_per_nd;
-    int dofs_per_blk;
-    int slf;
-    DynamicArray<T> strds;
-    DynamicArray<T> frsts;
-    int lcl_strd;
-  };
+  // explicit instantiations
+  template class AggregateNumberingOf<int>;
+  template class AggregateNumberingOf<long>;
   // this assumes that the ranks returned by a sharing
   //  do not change when the pcu comm changes
   //  if the sharing can handle the pcu comm changing
@@ -288,16 +247,11 @@ namespace apf
     getAll(e,&data[0]);
     return data[nd*cmps + cmp];
   }
-  // explicit instantiations
-  template class AggregateNumberingOf<int>;
-  template class AggregateNumberingOf<long>;
-  typedef AggregateNumberingOf<int> AggNumbering;
-  typedef AggregateNumberingOf<long> GlobalAggNumbering;
-  Numbering * createAggNumbering(Field * f,
-                                 int blocks,
-                                 int dofs_per_block,
-                                 MPI_Comm cm,
-                                 Sharing * share)
+  AggNumbering * createAggNumbering(Field * f,
+                                    int blocks,
+                                    int dofs_per_block,
+                                    MPI_Comm cm,
+                                    Sharing * share)
   {
     bool dlt = false;
     if(!share)
@@ -330,13 +284,13 @@ namespace apf
     f->getMesh()->addNumbering(n);
     return n;
   }
-  Numbering * createAggNumbering(Mesh * m,
-                                 const char * name,
-                                 FieldShape * shape,
-                                 int blocks,
-                                 int dofs_per_block,
-                                 MPI_Comm cm,
-                                 Sharing * share)
+  AggNumbering * createAggNumbering(Mesh * m,
+                                    const char * name,
+                                    FieldShape * shape,
+                                    int blocks,
+                                    int dofs_per_block,
+                                    MPI_Comm cm,
+                                    Sharing * share)
   {
     bool dlt = false;
     if(!share)
@@ -364,4 +318,17 @@ namespace apf
     m->addNumbering(n);
     return n;
   }
+  /* Public API */
+  Numbering * getNumbering(AggNumbering * n)
+  {
+    return static_cast<Numbering*>(n);
+  }
+  int countBlocks(AggNumbering * n)
+  {
+    return n->blockSize();
+  }
+  int countDOFsPerBlock(AggNumbering * n)
+  {
+    return n->blockSize();
+  }
 }
diff --git a/apf/apfAggregateNumbering.h b/apf/apfAggregateNumbering.h
index 1989859e2..ff2715fb5 100644
--- a/apf/apfAggregateNumbering.h
+++ b/apf/apfAggregateNumbering.h
@@ -2,21 +2,36 @@
 #define APF_AGGREGATE_NUMBERING_H_
 #include "apfNew.h"
 #include "apfMesh.h"
+#include "apfNumbering.h"
 #include <PCU.h>
 namespace apf
 {
-  Numbering * createAggNumbering(Field * f,
-                                 int blocks,
-                                 int dofs_per_block,
-                                 MPI_Comm cm,
-                                 Sharing * share = NULL);
-  Numbering * createAggNumbering(Mesh * m,
-                                 const char * name,
-                                 FieldShape * shape,
-                                 int blocks,
-                                 int dofs_per_block,
-                                 MPI_Comm cm,
-                                 Sharing * share = NULL);
+  // class declaration
+  template <class T>
+  class AggregateNumberingOf;
+  typedef AggregateNumberingOf<int> AggNumbering;
+  typedef AggregateNumberingOf<long> GlobalAggNumbering;
+  // numbering creation functions
+  AggNumbering * createAggNumbering(Field * f,
+                                    int blocks,
+                                    int dofs_per_block,
+                                    MPI_Comm cm,
+                                    Sharing * share = NULL);
+  AggNumbering * createAggNumbering(Mesh * m,
+                                    const char * name,
+                                    FieldShape * shape,
+                                    int blocks,
+                                    int dofs_per_block,
+                                    MPI_Comm cm,
+                                    Sharing * share = NULL);
+  /*
+   * @brief Since the class implementation is not public
+   *        we need an API to up-cast AggNumbering to
+   *        Numbering.
+   */
+  Numbering * getNumbering(AggNumbering * n);
+  int countBlocks(AggNumbering * n);
+  int countDOFsPerBlock(AggNumbering * n);
 }
 #endif
 /******************************************************************************
diff --git a/apf/apfAggregateNumberingClass.h b/apf/apfAggregateNumberingClass.h
new file mode 100644
index 000000000..ae6e4c1dd
--- /dev/null
+++ b/apf/apfAggregateNumberingClass.h
@@ -0,0 +1,53 @@
+#ifndef APF_AGGREGATE_NUMBERING_CLASS_H_
+#define APF_AGGREGATE_NUMBERING_CLASS_H_
+#include "apfFieldData.h"
+#include "apfNumberingClass.h"
+namespace apf
+{
+  template <class T>
+  class AggregateNumberingOf : public NumberingOf<T>
+  {
+  public:
+    AggregateNumberingOf()
+      : NumberingOf<T>()
+      , nd_ids(NULL)
+      , shr(NULL)
+      , blks_per_nd(0)
+      , dofs_per_blk(0)
+      , slf(-1)
+      , strds()
+      , frsts()
+      , lcl_strd(0)
+    { }
+    void init(const char * n,
+              Mesh * m,
+              Sharing * sh,
+              FieldShape * s,
+              int blks,
+              int bs);
+    void init(Field * f, Sharing * sh, int blks, int bs);
+    void globalize();
+    virtual void getAll(MeshEntity * e, T * dat);
+    virtual T get(MeshEntity * e, int nd, int cmp);
+    virtual void set(MeshEntity*,int,int,T) {}
+    Sharing * getSharing() const { return shr; }
+    void setSharing(Sharing * s) { shr = s; }
+    int countBlocks() const { return blks_per_nd; }
+    int blockSize() const { return dofs_per_blk; }
+    T getLocalStride() const { return lcl_strd; }
+    T getScopeStride() const { return strds[slf]; }
+    T getLocalFirstDof() const { return frsts[slf]; }
+    T getStride(int peer) const { return strds[peer]; };
+    T getFirstDof(int peer) const { return frsts[peer]; }
+  private:
+    FieldDataOf<T> * nd_ids;
+    Sharing * shr;
+    int blks_per_nd;
+    int dofs_per_blk;
+    int slf;
+    DynamicArray<T> strds;
+    DynamicArray<T> frsts;
+    int lcl_strd;
+  };
+}
+#endif