diff --git a/tools/install_venv.py b/tools/install_venv.py
index 88b1963..ae4ecfe 100644
--- a/tools/install_venv.py
+++ b/tools/install_venv.py
@@ -33,7 +33,7 @@ def print_help(venv, root):
     To activate the OpenStack virtualenv for the extent of your current shell
     session you can run:
 
-    $ source %s/bin/activate
+    $ . %s/bin/activate
 
     Or, if you prefer, you can run commands in the virtualenv on a case by case
     basis by running: