diff --git a/src/c/libstl/stlb_read.c b/src/c/libstl/stlb_read.c
index fc7f303..483d3c5 100644
--- a/src/c/libstl/stlb_read.c
+++ b/src/c/libstl/stlb_read.c
@@ -25,7 +25,9 @@ static void foug_stlb_read_facets(foug_stlb_geom_input_t* geom,
   }
 }
 
-int foug_stlb_read(foug_stlb_geom_input_t* geom, foug_transfer_t* trsf)
+int foug_stlb_read(foug_stlb_geom_input_t* geom,
+                   foug_transfer_t* trsf,
+                   foug_endianness_t byte_order)
 {
   uint32_t total_facet_count;
   size_t accum_facet_count_read;
@@ -35,6 +37,8 @@ int foug_stlb_read(foug_stlb_geom_input_t* geom, foug_transfer_t* trsf)
     return FOUG_DATAX_NULL_BUFFER_ERROR;
   if (trsf->buffer_size < FOUG_STLB_MIN_CONTENTS_SIZE)
     return FOUG_DATAX_INVALID_BUFFER_SIZE_ERROR;
+  if (byte_order != FOUG_LITTLE_ENDIAN)
+    return FOUG_STLB_READ_UNSUPPORTED_BYTE_ORDER;
 
   /* Read header */
   {
diff --git a/src/c/libstl/stlb_read.h b/src/c/libstl/stlb_read.h
index 9c93f6f..42ac3e3 100644
--- a/src/c/libstl/stlb_read.h
+++ b/src/c/libstl/stlb_read.h
@@ -3,6 +3,7 @@
 
 #include "stl_global.h"
 #include "stlb_triangle.h"
+#include "../endian.h"
 #include "../transfer.h"
 
 /* foug_stlb_geom_input */
@@ -18,10 +19,12 @@ struct foug_stlb_geom_input
 
 /* foug_stlb_read() */
 FOUG_DATAX_LIBSTL_EXPORT int foug_stlb_read(foug_stlb_geom_input_t* geom,
-                                            foug_transfer_t* trsf);
+                                            foug_transfer_t* trsf,
+                                            foug_endianness_t byte_order);
 
 /* Specific error codes returned by foug_stlb_read() */
 #define FOUG_STLB_READ_HEADER_WRONG_SIZE_ERROR   1
 #define FOUG_STLB_READ_FACET_COUNT_ERROR         2
+#define FOUG_STLB_READ_UNSUPPORTED_BYTE_ORDER    3
 
 #endif /* FOUG_DATAX_C_LIBSTL_STLB_READ_H */
diff --git a/src/c/libstl/stlb_write.c b/src/c/libstl/stlb_write.c
index ab48b9f..3c30787 100644
--- a/src/c/libstl/stlb_write.c
+++ b/src/c/libstl/stlb_write.c
@@ -25,7 +25,8 @@ static void foug_stlb_write_facets(const foug_stlb_geom_output_t* geom,
   } /* end for */
 }
 
-int foug_stlb_write(const foug_stlb_geom_output_t* geom, foug_transfer_t* trsf)
+int foug_stlb_write(const foug_stlb_geom_output_t* geom,
+                    foug_transfer_t* trsf, foug_endianness_t byte_order)
 {
   uint32_t facet_count;
   uint32_t i_facet;
@@ -41,6 +42,8 @@ int foug_stlb_write(const foug_stlb_geom_output_t* geom, foug_transfer_t* trsf)
     return FOUG_STLB_WRITE_NULL_GET_TRIANGLE_COUNT_FUNC;
   if (geom == NULL || geom->get_triangle_func == NULL)
     return FOUG_STLB_WRITE_NULL_GET_TRIANGLE_FUNC;
+  if (byte_order != FOUG_LITTLE_ENDIAN/* && byte_order != FOUG_BIG_ENDIAN*/)
+    return FOUG_STLB_WRITE_UNSUPPORTED_BYTE_ORDER;
 
   /* Write header */
   {
@@ -56,7 +59,10 @@ int foug_stlb_write(const foug_stlb_geom_output_t* geom, foug_transfer_t* trsf)
 
   /* Write facet count */
   facet_count = geom->get_triangle_count_func(geom);
-  foug_encode_uint32_le(facet_count, trsf->buffer);
+  if (byte_order == FOUG_LITTLE_ENDIAN)
+    foug_encode_uint32_le(facet_count, trsf->buffer);
+  else
+    foug_encode_uint32_be(facet_count, trsf->buffer);
   if (foug_stream_write(&trsf->stream, trsf->buffer, sizeof(uint32_t), 1) != 1)
     return FOUG_DATAX_STREAM_ERROR;
 
diff --git a/src/c/libstl/stlb_write.h b/src/c/libstl/stlb_write.h
index 909fd00..6fed163 100644
--- a/src/c/libstl/stlb_write.h
+++ b/src/c/libstl/stlb_write.h
@@ -3,6 +3,7 @@
 
 #include "stl_global.h"
 #include "stlb_triangle.h"
+#include "../endian.h"
 #include "../transfer.h"
 
 /* foug_stlb_geom_output */
@@ -10,17 +11,19 @@ typedef struct foug_stlb_geom_output foug_stlb_geom_output_t;
 struct foug_stlb_geom_output
 {
   void* cookie;
-  void     (*get_header_func)        (const foug_stlb_geom_output_t*, uint8_t*);
+  void     (*get_header_func)        (const foug_stlb_geom_output_t*, uint8_t*); /* Optional */
   uint32_t (*get_triangle_count_func)(const foug_stlb_geom_output_t*);
   void     (*get_triangle_func)      (const foug_stlb_geom_output_t*, uint32_t, foug_stlb_triangle_t*);
 };
 
 /* foug_stlb_write() */
 FOUG_DATAX_LIBSTL_EXPORT int foug_stlb_write(const foug_stlb_geom_output_t* geom,
-                                             foug_transfer_t* trsf);
+                                             foug_transfer_t* trsf,
+                                             foug_endianness_t byte_order);
 
 /* Specific error codes returned by foug_stlb_write() */
 #define FOUG_STLB_WRITE_NULL_GET_TRIANGLE_COUNT_FUNC 1
 #define FOUG_STLB_WRITE_NULL_GET_TRIANGLE_FUNC       2
+#define FOUG_STLB_WRITE_UNSUPPORTED_BYTE_ORDER       3
 
 #endif /* FOUG_DATAX_C_LIBSTL_STLB_WRITE_H */