diff --git a/bin/packstack b/bin/packstack
index a68cce651..102778f24 100755
--- a/bin/packstack
+++ b/bin/packstack
@@ -6,7 +6,7 @@ try:
     import packstack
 except ImportError:
     # packstack isn't installed, running from source checkout
-    sys.path.append(os.path.join(os.path.split(sys.argv[0])[0], ".."))
+    sys.path.insert(0, os.path.join(os.path.split(sys.argv[0])[0], ".."))
     import packstack
 
 os.environ["INSTALLER_PROJECT_DIR"] = os.path.abspath(os.path.split(packstack.__file__)[0])