diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ffd337593f586d31075912a7c58c44f1a917a910..d5357198924e722a65a91911d0b45c3c19a52b43 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -25,7 +25,10 @@ after merging the changes, too.
 
 The preferred way to discuss in the IRC channel ([#gluon] on irc.hackint.org)
 or on the [mailing list], however, you can also open a new issue on Github to
-discuss there.
+discuss there. We maintain a [list of rejected
+features](https://github.com/freifunk-gluon/gluon/issues?q=label%3Arejected)
+and we'd like to kindly ask you to review it first. In general, looking for
+duplicates may save you some time.
 
 Develop on top of master
 ------------------------