diff --git a/wrappers/MATLAB/MATLABBuilder_OSX.m b/wrappers/MATLAB/MATLABBuilder_OSX.m
index c70f27d1..e59ec830 100644
--- a/wrappers/MATLAB/MATLABBuilder_OSX.m
+++ b/wrappers/MATLAB/MATLABBuilder_OSX.m
@@ -1,4 +1,3 @@
-
 %The path to the main folder of the CoolProp source
 path_to_src = '../../CoolProp/'
 
@@ -27,15 +26,17 @@
 	o_file = strrep(bare_files{i,1},'.cpp','.o');
     o_files = [o_files,' ',o_file];
     disp(file);
-    eval(['mex -DEXTERNC -c', include_string,' -outdir . ',file])
+    eval(['mex -largeArrayDims -DEXTERNC -c', include_string,' -outdir . ',file])
 end
 
 %Build the MEX files
-eval(['mex -v ', include_string,' Props.c ', o_files])
-eval(['mex -v ', include_string,' HAProps.c ', o_files])
+eval(['mex -largeArrayDims -v ', include_string,' Props.c ', o_files])
+eval(['mex -largeArrayDims -v ', include_string,' HAProps.c ', o_files])
+eval(['mex -largeArrayDims -v ', include_string,' PropsSI.c ', o_files])
+eval(['mex -largeArrayDims -v ', include_string,' PropsSIV.c ', o_files])
 
 %Clean up - delete the obj files
-delete('*.o')
+%delete('*.o')
 
 %Quit MATLAB
 %quit
diff --git a/wrappers/MATLAB/PropsSIV.c b/wrappers/MATLAB/PropsSIV.c
new file mode 100644
index 00000000..dab68253
--- /dev/null
+++ b/wrappers/MATLAB/PropsSIV.c
@@ -0,0 +1,122 @@
+#include "mex.h"   /*--This one is required*/
+
+/* Prototype for the Props function to be called.  Can't use the CoolProp.h header because there are a lot of
+   c++ parts in the header that cannot be easily hidden when compiling */
+double PropsSI(char *Output, char *Name1, double Prop1, char *Name2, double Prop2, char * Ref);
+double Props1(char *Output, char * Ref);
+long get_global_param_string(char*, char*);
+long get_fluid_param_string(char *fluid, char *param, char * Output);
+long get_standard_unit_system(void);
+void set_standard_unit_system(long);
+#include "GlobalConstants.h"
+#include "float.h"
+
+bool ValidNumber(double x)
+{
+    // Idea from http://www.johndcook.com/IEEE_exceptions_in_cpp.html
+    return (x <= DBL_MAX && x >= -DBL_MAX);
+};
+
+void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
+{
+    int npol,Nel;
+    int m,n,u,v,k,Output_len,Name1_len,Name2_len,Ref_len,Param_len;
+    int *c,status;
+    double *d,Prop1,Prop2,x,y;
+	char *Output,*Name1,*Name2,*Ref,*Param,errstr[1000],errstr2[1000],fluidslist[10000];
+    double val;
+    double *rval;
+    mxArray *cMat[1];
+    
+    double *pro1,*pro2;
+    size_t mrows1,ncols1,mrows2,ncols2;
+    size_t i;
+    
+    if (nrhs == 6 && mxIsChar (prhs[0]) && mxIsChar (prhs[1])  && mxIsChar (prhs[3])  && mxIsChar (prhs[5])  )
+    {
+        
+        pro1 = mxGetPr(prhs[2]);mrows1 = mxGetM(prhs[2]);ncols1 = mxGetN(prhs[2]);
+        pro2 = mxGetPr(prhs[4]);mrows2 = mxGetM(prhs[4]);ncols2 = mxGetN(prhs[4]);        
+       
+        if(!((mrows1==mrows2) && (ncols1==ncols2))){
+            mexErrMsgIdAndTxt( "MATLAB:PROSV",
+            "Val uses of not same size."); 
+        }
+        if(!(ncols1==1 && ncols2==1     )){
+            mexErrMsgIdAndTxt( "MATLAB:PROSV",
+                               "Not implemented for matrix input");
+        }
+        /* Create matrix for the return argument. */
+        plhs[0] = mxCreateDoubleMatrix(mrows1,ncols1, mxREAL);
+        rval = mxGetPr(plhs[0]);
+        
+        /* Get the refrigerant (it is a string) (+1 for the NULL terminator)*/
+        Ref_len=(mxGetM(prhs[5]) * mxGetN(prhs[5])) + 1;
+        Ref = mxCalloc(Ref_len, sizeof(char));
+        mxGetString(prhs[5], Ref, Ref_len);
+        
+        /* Get the output (it is a string) (+1 for the NULL terminator)*/
+        Output_len=(mxGetM(prhs[0]) * mxGetN(prhs[0])) + 1;
+        Output = mxCalloc(Output_len, sizeof(char));
+        mxGetString(prhs[0], Output, Output_len);
+        
+        Name1_len=(mxGetM(prhs[1]) * mxGetN(prhs[1])) + 1;
+        Name1 = mxCalloc(Name1_len, sizeof(char));
+        mxGetString(prhs[1], Name1, Name1_len);
+        
+        Name2_len=(mxGetM(prhs[3]) * mxGetN(prhs[3])) + 1;
+        Name2 = mxCalloc(Name2_len, sizeof(char));
+        mxGetString(prhs[3], Name2, Name2_len);
+
+        /*
+        Prop1 = mxGetScalar(prhs[2]);
+        Prop2 = mxGetScalar(prhs[4]);
+        */
+       
+        for(i=0;i<mrows1;++i){
+            Prop1 = pro1[i];
+            Prop2 = pro2[i];
+            val = PropsSI(Output,Name1,Prop1,Name2,Prop2,Ref);
+            if (ValidNumber(val))
+            {
+                rval[i]=val;
+                /* *mxGetPr(plhs[0]) = val;*/
+            } else{
+            get_global_param_string("errstring",errstr);
+            sprintf(errstr2,"CoolProp Error: %s",errstr);
+            mexErrMsgTxt(errstr2);
+            }
+
+        }
+        /* If it is a good value, return it */
+        /* Otherwise there was an error, return the CoolProp error*/
+       
+    }
+    else if (nrhs == 1 && mxIsChar (prhs[0]))
+    {
+        Ref_len=(mxGetM(prhs[0]) * mxGetN(prhs[0])) + 1;
+        Ref = mxCalloc(Ref_len, sizeof(char));
+        status = mxGetString(prhs[0], Ref, Ref_len);
+        
+        if (!strcmp(Ref,"FluidsList")){
+            get_global_param_string("FluidsList",fluidslist);
+        }
+        else if (!strcmp(Ref,"version")){
+            get_global_param_string("version",fluidslist);
+        }
+        else if (!strcmp(Ref,"gitrevision")){
+            get_global_param_string("gitrevision", fluidslist);
+        }
+        else
+        {
+            sprintf(errstr2,"single input is invalid: %s",Ref);
+            mexErrMsgTxt(errstr2);
+        }
+        plhs[0] = mxCreateString(fluidslist);
+        return;
+    }
+    else
+    {
+        mexErrMsgTxt("Props must either receive two strings or the signature Props(Output,Param1,Value1,Param2,Value2,FluidName)");
+    }
+}
diff --git a/wrappers/MATLAB/mexopts.sh b/wrappers/MATLAB/mexopts.sh
new file mode 100644
index 00000000..9abc31b3
--- /dev/null
+++ b/wrappers/MATLAB/mexopts.sh
@@ -0,0 +1,6 @@
+. ${MATLAB}/bin/mexopts.sh
+
+CFLAGS='-D_GNU_SOURCE  -fexceptions -fPIC -fno-omit-frame-pointer -pthread'
+CXXFLAGS='-D_GNU_SOURCE -fPIC -fno-omit-frame-pointer -pthread'
+CLIBS="-ldl ${CLIBS}"
+CXXLIBS="-ldl ${CXXLIBS}"
\ No newline at end of file