diff --git a/setup.py b/setup.py
index 329b7f2b..6a76b500 100644
--- a/setup.py
+++ b/setup.py
@@ -11,6 +11,7 @@
            'fake_filesystem_shutil',
            'fake_tempfile',
            'fake_filesystem_unittest']
+REQUIRES = ['mock']
 DESCRIPTION = 'Fakes file system modules for automated developer testing.'
 
 URL = "https://code.google.com/p/pyfakefs"
@@ -45,6 +46,7 @@
     name=NAME,
     version=__version__,
     py_modules=MODULES,
+    install_requires=REQUIRES,
 
     # metadata for upload to PyPI
     author=AUTHOR,