diff --git a/README.md b/README.md
index 80f3bd0d6..aa12edac4 100644
--- a/README.md
+++ b/README.md
@@ -57,6 +57,9 @@ doing:
 }
 ```
 
+This is included in all configs shared by this plugin, so can be omitted if
+extending them.
+
 The behaviour of some rules (specifically `no-deprecated-functions`) change
 depending on the version of `jest` being used.