diff --git a/docs/installation.rst b/docs/installation.rst
index 8cd253b15..21835815c 100644
--- a/docs/installation.rst
+++ b/docs/installation.rst
@@ -62,7 +62,7 @@ that the required dependencies are installed: ::
 **OSX**, system python is not recommended. brew's python also ships with pip  ::
 
     brew install pkg-config libffi openssl python
-    env LDFLAGS="-L$(brew --prefix openssl)/lib" CFLAGS="-I$(brew --prefix openssl)/include" pip install cryptography==1.7.2
+    env LDFLAGS="-L$(brew --prefix openssl)/lib" CFLAGS="-I$(brew --prefix openssl)/include" pip install cryptography==1.9
 
 **Windows** isn't officially supported at this point, but if you want to
 attempt it, download `get-pip.py <https://bootstrap.pypa.io/get-pip.py>`_, and run ``python get-pip.py`` which may need admin access. Then run the following: ::