diff --git a/Grid_simd.h b/Grid_simd.h
new file mode 100644
index 00000000..aa16286b
--- /dev/null
+++ b/Grid_simd.h
@@ -0,0 +1,102 @@
+#ifndef GRID_SIMD_H
+#define GRID_SIMD_H
+
+////////////////////////////////////////////////////////////////////////
+// Define scalar and vector floating point types
+//
+// Scalar:   RealF, RealD, ComplexF, ComplexD
+//
+// Vector:  vRealF, vRealD, vComplexF, vComplexD
+//
+// Vector types are arch dependent
+////////////////////////////////////////////////////////////////////////
+
+namespace dpo {
+
+  typedef  float  RealF;
+  typedef  double RealD;
+  typedef  RealF  Real;
+  
+  typedef std::complex<RealF> ComplexF;
+  typedef std::complex<RealD> ComplexD;
+  typedef std::complex<Real>  Complex;
+  
+  
+  class Zero{};
+  static Zero zero;
+  template<class itype> inline void ZeroIt(itype &arg){ arg=zero;};
+  template<>            inline void ZeroIt(ComplexF &arg){ arg=0; };
+  template<>            inline void ZeroIt(ComplexD &arg){ arg=0; };
+  template<>            inline void ZeroIt(RealF &arg){ arg=0; };
+  template<>            inline void ZeroIt(RealD &arg){ arg=0; };
+
+
+  ////////////////////////////////////////////////////////////
+  // SIMD Alignment controls
+  ////////////////////////////////////////////////////////////
+#ifdef HAVE_VAR_ATTRIBUTE_ALIGNED
+#define ALIGN_DIRECTIVE(A) __attribute__ ((aligned(A)))
+#else
+#define ALIGN_DIRECTIVE(A) __declspec(align(A))
+#endif
+
+#ifdef SSE2
+#include <pmmintrin.h>
+#define SIMDalign ALIGN_DIRECTIVE(16)
+#endif
+
+#if defined(AVX1) || defined (AVX2)
+#include <immintrin.h>
+#define SIMDalign ALIGN_DIRECTIVE(32)
+#endif
+
+#ifdef AVX512
+#include <immintrin.h>
+#define SIMDalign ALIGN_DIRECTIVE(64)
+#endif
+
+#if defined (SSE2)
+    typedef __m128 fvec;
+    typedef __m128d dvec;
+    typedef __m128 cvec;
+    typedef __m128d zvec;
+#endif
+#if defined (AVX1) || defined (AVX2)
+    typedef __m256 fvec;
+    typedef __m256d dvec;
+    typedef __m256 cvec;
+    typedef __m256d zvec;
+#endif
+#if defined (AVX512)
+    typedef __m512  fvec;
+    typedef __m512d dvec;
+    typedef __m512  cvec;
+    typedef __m512d zvec;
+#endif
+#if defined (QPX)
+    typedef float  fvec __attribute__ ((vector_size (16))); // QPX has same SIMD width irrespective of precision
+    typedef float  cvec __attribute__ ((vector_size (16)));
+    
+    typedef vector4double dvec;
+    typedef vector4double zvec;
+#endif
+#if defined (AVX1) || defined (AVX2) || defined (AVX512)
+    inline void v_prefetch0(int size, const char *ptr){
+          for(int i=0;i<size;i+=64){ //  Define L1 linesize above// What about SSE?
+            _mm_prefetch(ptr+i+4096,_MM_HINT_T1);
+            _mm_prefetch(ptr+i+512,_MM_HINT_T0);
+          }
+    }
+#else 
+    inline void v_prefetch0(int size, const char *ptr){};
+#endif
+
+};
+
+#include <Grid_vRealF.h>
+#include <Grid_vRealD.h>
+#include <Grid_vComplexF.h>
+#include <Grid_vComplexD.h>
+
+
+#endif