diff --git a/docs/installation.rst b/docs/installation.rst
index 259d5928..be92795f 100644
--- a/docs/installation.rst
+++ b/docs/installation.rst
@@ -5,7 +5,10 @@ Installation
 Python & OS Support
 ###################
 
-PyDocX is supported and tested with CPython versions 2.6, 2.7, 3.3, 3.4, and pypy.
+PyDocX is supported and tested with CPython versions 2.6, 2.7, 3.3, 3.4, and
+PyPy 2.5 (Python 2.7 compatible). These are the versions exercised by the
+CI matrix (see ``.travis.yml`` and ``tox.ini``); other Python versions may
+work but are not officially tested.
 
 PyDocX is supported and tested with Linux and Windows.