diff --git a/lib/AlignedAllocator.h b/lib/AlignedAllocator.h
index 8f69971d..d0de1ec3 100644
--- a/lib/AlignedAllocator.h
+++ b/lib/AlignedAllocator.h
@@ -40,14 +40,6 @@ Author: Peter Boyle <paboyle@ph.ed.ac.uk>
 #include <mm_malloc.h>
 #endif
 
-#ifdef GRID_COMMS_SHMEM
-extern "C" { 
-#include <mpp/shmem.h>
-extern void * shmem_align(size_t, size_t);
-extern void  shmem_free(void *);
-}
-#endif
-
 namespace Grid {
 
 ////////////////////////////////////////////////////////////////////
@@ -65,28 +57,81 @@ public:
   typedef _Tp        value_type;
 
   template<typename _Tp1>  struct rebind { typedef alignedAllocator<_Tp1> other; };
-
   alignedAllocator() throw() { }
-
   alignedAllocator(const alignedAllocator&) throw() { }
-
   template<typename _Tp1> alignedAllocator(const alignedAllocator<_Tp1>&) throw() { }
-
   ~alignedAllocator() throw() { }
-
   pointer       address(reference __x)       const { return &__x; }
-  //  const_pointer address(const_reference __x) const { return &__x; }
-
   size_type  max_size() const throw() { return size_t(-1) / sizeof(_Tp); }
 
   pointer allocate(size_type __n, const void* _p= 0)
   { 
+#ifdef HAVE_MM_MALLOC_H
+    _Tp * ptr = (_Tp *) _mm_malloc(__n*sizeof(_Tp),128);
+#else
+    _Tp * ptr = (_Tp *) memalign(128,__n*sizeof(_Tp));
+#endif
+
+    _Tp tmp;
+#ifdef GRID_NUMA
+#pragma omp parallel for schedule(static)
+  for(int i=0;i<__n;i++){
+    ptr[i]=tmp;
+  }
+#endif 
+    return ptr;
+  }
+
+  void deallocate(pointer __p, size_type) { 
+#ifdef HAVE_MM_MALLOC_H
+    _mm_free((void *)__p); 
+#else
+    free((void *)__p);
+#endif
+  }
+  void construct(pointer __p, const _Tp& __val) { };
+  void construct(pointer __p) { };
+  void destroy(pointer __p) { };
+};
+template<typename _Tp>  inline bool operator==(const alignedAllocator<_Tp>&, const alignedAllocator<_Tp>&){ return true; }
+template<typename _Tp>  inline bool operator!=(const alignedAllocator<_Tp>&, const alignedAllocator<_Tp>&){ return false; }
+
+//////////////////////////////////////////////////////////////////////////////////////////
+// MPI3 : comms must use shm region
+// SHMEM: comms must use symmetric heap
+//////////////////////////////////////////////////////////////////////////////////////////
 #ifdef GRID_COMMS_SHMEM
-
-    _Tp *ptr = (_Tp *) shmem_align(__n*sizeof(_Tp),64);
-
-
+extern "C" { 
+#include <mpp/shmem.h>
+extern void * shmem_align(size_t, size_t);
+extern void  shmem_free(void *);
+}
 #define PARANOID_SYMMETRIC_HEAP
+#endif
+
+template<typename _Tp>
+class commAllocator {
+public: 
+  typedef std::size_t     size_type;
+  typedef std::ptrdiff_t  difference_type;
+  typedef _Tp*       pointer;
+  typedef const _Tp* const_pointer;
+  typedef _Tp&       reference;
+  typedef const _Tp& const_reference;
+  typedef _Tp        value_type;
+
+  template<typename _Tp1>  struct rebind { typedef commAllocator<_Tp1> other; };
+  commAllocator() throw() { }
+  commAllocator(const commAllocator&) throw() { }
+  template<typename _Tp1> commAllocator(const commAllocator<_Tp1>&) throw() { }
+  ~commAllocator() throw() { }
+  pointer       address(reference __x)       const { return &__x; }
+  size_type  max_size() const throw() { return size_t(-1) / sizeof(_Tp); }
+
+#ifdef GRID_COMMS_SHMEM
+  pointer allocate(size_type __n, const void* _p= 0)
+  { 
+    _Tp *ptr = (_Tp *) shmem_align(__n*sizeof(_Tp),64);
 #ifdef PARANOID_SYMMETRIC_HEAP
     static void * bcast;
     static long  psync[_SHMEM_REDUCE_SYNC_SIZE];
@@ -99,51 +144,52 @@ public:
       BACKTRACEFILE();
       exit(0);
     }
-
     assert( bcast == (void *) ptr);
-
 #endif 
+    return ptr;
+  }
+  void deallocate(pointer __p, size_type) { 
+    shmem_free((void *)__p);
+  }
+#elif defined(GRID_COMMS_MPI3)
+  pointer allocate(size_type __n, const void* _p= 0)
+  { 
+#error "implement MPI3 windowed allocate"
+    
+  }
+  void deallocate(pointer __p, size_type) { 
+#error "implement MPI3 windowed allocate"
+  }
 #else
-
+  pointer allocate(size_type __n, const void* _p= 0)
 #ifdef HAVE_MM_MALLOC_H
     _Tp * ptr = (_Tp *) _mm_malloc(__n*sizeof(_Tp),128);
 #else
     _Tp * ptr = (_Tp *) memalign(128,__n*sizeof(_Tp));
 #endif
-
-#endif
-    _Tp tmp;
-#ifdef GRID_NUMA
-#pragma omp parallel for schedule(static)
-  for(int i=0;i<__n;i++){
-    ptr[i]=tmp;
-  }
-#endif 
     return ptr;
   }
-
   void deallocate(pointer __p, size_type) { 
-#ifdef GRID_COMMS_SHMEM
-    shmem_free((void *)__p);
-#else
 #ifdef HAVE_MM_MALLOC_H
     _mm_free((void *)__p); 
 #else
     free((void *)__p);
-#endif
 #endif
   }
+#endif
   void construct(pointer __p, const _Tp& __val) { };
   void construct(pointer __p) { };
-
   void destroy(pointer __p) { };
 };
+template<typename _Tp>  inline bool operator==(const commAllocator<_Tp>&, const commAllocator<_Tp>&){ return true; }
+template<typename _Tp>  inline bool operator!=(const commAllocator<_Tp>&, const commAllocator<_Tp>&){ return false; }
 
-template<typename _Tp>  inline bool
-operator==(const alignedAllocator<_Tp>&, const alignedAllocator<_Tp>&){ return true; }
-
-template<typename _Tp>  inline bool
-operator!=(const alignedAllocator<_Tp>&, const alignedAllocator<_Tp>&){ return false; }
+////////////////////////////////////////////////////////////////////////////////
+// Template typedefs
+////////////////////////////////////////////////////////////////////////////////
+template<class T> using Vector    = std::vector<T,alignedAllocator<T> >;           
+template<class T> using commVector = std::vector<T,commAllocator<T> >;              
+template<class T> using Matrix = std::vector<std::vector<T,alignedAllocator<T> > >;
     
 }; // namespace Grid
 #endif