diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index fbc007949c..d74816990b 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -5,6 +5,8 @@ These are notable changes in edx-platform.  This is a rolling list of changes,
 in roughly chronological order, most recent first.  Add your entries at or near
 the top.  Include a label indicating the component affected.
 
+XModule: Only write out assets files if the contents have changed.
+
 XModule: Don't delete generated xmodule asset files when compiling (for
 instance, when XModule provides a coffeescript file, don't delete
 the associated javascript)
diff --git a/common/lib/xmodule/xmodule/static_content.py b/common/lib/xmodule/xmodule/static_content.py
index 42fef65b11..7662499c16 100755
--- a/common/lib/xmodule/xmodule/static_content.py
+++ b/common/lib/xmodule/xmodule/static_content.py
@@ -4,6 +4,7 @@ This module has utility functions for gathering up the static content
 that is defined by XModules and XModuleDescriptors (javascript and css)
 """
 
+import logging
 import hashlib
 import os
 import errno
@@ -15,6 +16,9 @@ from path import path
 from xmodule.x_module import XModuleDescriptor
 
 
+LOG = logging.getLogger(__name__)
+
+
 def write_module_styles(output_root):
     return _write_styles('.xmodule_display', output_root, _list_modules())
 
@@ -140,7 +144,13 @@ def _write_files(output_root, contents, generated_suffix_map=None):
         (output_root / extra_file).remove_p()
 
     for filename, file_content in contents.iteritems():
-        (output_root / filename).write_bytes(file_content)
+        output_file = output_root / filename
+
+        if not output_file.isfile() or output_file.read_md5() != hashlib.md5(file_content).digest():
+            LOG.debug("Writing %s", output_file)
+            output_file.write_bytes(file_content)
+        else:
+            LOG.debug("%s unchanged, skipping", output_file)
 
 
 def main():