diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
index 66766512..852e44be 100644
--- a/CONTRIBUTING.rst
+++ b/CONTRIBUTING.rst
@@ -54,7 +54,7 @@ Install Flask as an editable package using the current source::
 
 Then you can run the testsuite with::
 
-    pytest
+    pytest tests/
 
 With only pytest installed, a large part of the testsuite will get skipped
 though.  Whether this is relevant depends on which part of Flask you're working