diff --git a/docs/source/config/intro.rst b/docs/source/config/intro.rst
index c4f5473..95d9989 100644
--- a/docs/source/config/intro.rst
+++ b/docs/source/config/intro.rst
@@ -104,6 +104,9 @@ To see all of these abbreviated options, run::
     ipython notebook --help
     # etc.
 
+Options specified at the command line, in either format, override
+options set in a configuration file.
+
 The config magic
 ----------------