diff --git a/src/geoflow/stats.C b/src/geoflow/stats.C
index 87efd66..8e3a1f4 100644
--- a/src/geoflow/stats.C
+++ b/src/geoflow/stats.C
@@ -25,6 +25,7 @@
 
 
 #include <cmath>
+#include <sstream>
 
 //#include <advisor-annotate.h>
 
@@ -44,6 +45,7 @@ StatProps::StatProps(ElementsHashTable *_ElemTable, NodeHashTable* _NodeTable):
     xyminmax[0] = xyminmax[1] = xyminmax[2] = xyminmax[3] = hxyminmax = 0.0;
     lhs.refnum = lhs.runid = -1;
     runid = -1;
+    output_prefix="";
 }
 StatProps::StatProps(ElementsHashTable *_ElemTable, NodeHashTable* _NodeTable, const H5::CommonFG *parent, const  string group_name):
     EleNodeRef(_ElemTable, _NodeTable)
@@ -56,6 +58,7 @@ StatProps::StatProps(ElementsHashTable *_ElemTable, NodeHashTable* _NodeTable, c
     xyminmax[0] = xyminmax[1] = xyminmax[2] = xyminmax[3] = hxyminmax = 0.0;
     lhs.refnum = lhs.runid = -1;
     runid = -1;
+    output_prefix="";
     h5read(parent, group_name);
 }
 StatProps::~StatProps()
@@ -511,10 +514,11 @@ void out_final_stats(TimeProps* timeprops, StatProps* statprops)
     int cpuminutes = (cputime % 3600) / 60;
     int cpuseconds = cputime % 60;
 
-    char filename[256];
-    sprintf(filename, "finalstats.%06d", statprops->runid);
+    ostringstream filename;
+
+    filename<<statprops->output_prefix<<"finalstats."<<setw(6)<< setfill('0') <<internal<<statprops->runid<<std::ends;
+    FILE *fp = fopen(filename.str().c_str(), "wt");
 //printf("runid=%d\n",statprops->runid);
-    FILE* fp = fopen(filename, "w");
 //print    runid  xC yC   rC  area maxh    wall time       cpu time
     fprintf(fp, "%6d   %E %E   %E   %E   %E   %E   %d:%02d:%02d   %d:%02d:%02d\n", statprops->runid, statprops->xcen,
             statprops->ycen, statprops->rmean, statprops->area, statprops->hmax, statprops->timereached, wallhours,
@@ -631,6 +635,7 @@ void StatProps::h5write(H5::CommonFG *parent, string group_name) const
     TiH5_writeDoubleAttribute(group, timereached);
     TiH5_writeDoubleAttribute(group, xyminmax[4]);
     TiH5_writeDoubleAttribute(group, hxyminmax);
+    TiH5_writeStringAttribute(group, output_prefix);
 
     lhs.h5write(&group);
 }
@@ -666,6 +671,7 @@ void StatProps::h5read(const H5::CommonFG *parent, const  string group_name)
     TiH5_readDoubleAttribute(group, timereached);
     TiH5_readDoubleAttribute(group, xyminmax[4]);
     TiH5_readDoubleAttribute(group, hxyminmax);
+    TiH5_readStringAttribute(group, output_prefix);
 
     lhs.h5read(&group);
 
diff --git a/src/header/stats.hpp b/src/header/stats.hpp
index fc5314e..001afd6 100644
--- a/src/header/stats.hpp
+++ b/src/header/stats.hpp
@@ -113,6 +113,8 @@ class StatProps: public EleNodeRef
     //! the latin hypercube sampling specific stats
     LHS_Props lhs;
 
+    std::string output_prefix;
+
     //! the constructor initializes a few statistics
     StatProps(ElementsHashTable *_ElemTable, NodeHashTable* _NodeTable);
     //! the constructor from hd5
diff --git a/src/main/titan.py b/src/main/titan.py
index 8ed6c9a..439cf72 100644
--- a/src/main/titan.py
+++ b/src/main/titan.py
@@ -576,9 +576,12 @@ def __init__(self,overwrite_output=False):
                 },
                 'runid':{'desc':'',
                     'validator':VarType(int).chk
-                },          
+                },
+                'output_prefix':{'desc':'',
+                    'validator':VarTypeString
+                },      
             },
-            defaultParameters={'edge_height':None, 'test_height':None, 'test_location':None, 'runid':-1}
+            defaultParameters={'edge_height':None, 'test_height':None, 'test_location':None, 'runid':-1, 'output_prefix':''}
         )
         self.setStatProps()
         #setOutlineProps
@@ -1046,6 +1049,7 @@ def check_and_remove_filedir_by_wildcard(filename):
             ui_StatProps['edge_height'], ui_StatProps['test_height'],
             ui_StatProps['test_location'][0], ui_StatProps['test_location'][1])
         self.sim.get_statprops().runid=ui_StatProps['runid']
+        self.sim.get_statprops().output_prefix=ui_StatProps['output_prefix']
         
         #######################################################################
         # ui_OutlineProps
diff --git a/src/tecplot/outsum.C b/src/tecplot/outsum.C
index be80223..63cabbd 100644
--- a/src/tecplot/outsum.C
+++ b/src/tecplot/outsum.C
@@ -22,14 +22,16 @@
 #include "../header/hpfem.h"
 #include "../header/stats.hpp"
 
+#include <sstream>
 #define ADAM_HEIGHT_FRAC 0.02
 
 void output_summary(TimeProps* timeprops, StatProps* statprops, int savefileflag)
 {
     //FILE *fp=fopen("output_summary.readme","a");
-    char filename[256];
-    sprintf(filename, "output_summary.%06d", statprops->runid);
-    FILE *fp = fopen(filename, "a");
+    ostringstream filename;
+
+    filename<<statprops->output_prefix<<"output_summary."<<setw(6)<< setfill('0') <<internal<<statprops->runid<<std::ends;
+    FILE *fp = fopen(filename.str().c_str(), "at");
     
     if(timeprops->ifstart())
         fprintf(fp, "Summary of Output from Titan2D\n\n");
@@ -50,9 +52,10 @@ void output_summary(TimeProps* timeprops, StatProps* statprops, int savefileflag
 
 void output_stoch_stats(MatProps* matprops, StatProps* statprops)
 {
-    char filename[128];
-    sprintf(filename, "statout_lhs.%02d", statprops->lhs.refnum);
-    FILE *fp = fopen(filename, "w");
+    ostringstream filename;
+
+    filename<<statprops->output_prefix<<"statout_lhs."<<setw(6)<< setfill('0') <<internal<<statprops->runid<<std::ends;
+    FILE *fp = fopen(filename.str().c_str(), "w");
     fprintf(fp, "%2d %6d %16.10g %16.10g %16.10g %16.10g %16.10g %16.10g %16.10g\n", statprops->lhs.refnum,
             statprops->lhs.runid, statprops->timereached, statprops->vstar * matprops->Vslump, statprops->hmax,
             statprops->xcen, statprops->ycen, statprops->xyminmax[1] - statprops->xyminmax[0],