diff --git a/BUILDING.txt b/BUILDING.md
similarity index 100%
rename from BUILDING.txt
rename to BUILDING.md
diff --git a/README.md b/README.md
index 78b7367562..552cdef866 100644
--- a/README.md
+++ b/README.md
@@ -12,7 +12,7 @@ If it breaks, you get to keep *both* pieces.
 
 # Compiling OpenSim
 
-Please see BUILDING.txt if you downloaded a source distribution and 
+Please see BUILDING.md if you downloaded a source distribution and 
 need to build OpenSim before running it.
 
 # Running OpenSim on Windows