diff --git a/setup.py b/setup.py
index c0a73f5..987bffa 100644
--- a/setup.py
+++ b/setup.py
@@ -21,6 +21,8 @@ setup(
             'source_dir': ('setup.py', 'doc')
         }
     },
-    install_requires=['lmfit', 'pandas', 'numpy', 'scipy', 'mongoengine'],
+    install_requires=[
+        'lmfit', 'pandas', 'numpy', 'scipy', 'mongoengine', 'sphinx'
+    ],
     packages=['pytestpavement'],
 )