diff --git a/INSTALL.md b/INSTALL.md
index 974a2809c..a3d16a6d6 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -178,4 +178,4 @@ tutorials on how to programmatically use Mapnik.
 
 ### Contributers
 
-Read docs/contributing.markdown for resources for getting involved with Mapnik development.
+Read docs/contributing.md for resources for getting involved with Mapnik development.
diff --git a/docs/contributing.markdown b/docs/contributing.md
similarity index 100%
rename from docs/contributing.markdown
rename to docs/contributing.md
diff --git a/docs/design.markdown b/docs/design.md
similarity index 100%
rename from docs/design.markdown
rename to docs/design.md