diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 0eefec23d4..faf4fb6029 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -14,6 +14,14 @@ These guidelines are meant to be a living document that should be changed and ad
 
 These guidelines mainly applies to Typesafe’s “mature” projects - not necessarily to projects of the type ‘collection of scripts’ etc.
 
+## Branches summary
+
+Depending on which version (or sometimes module) you want to work on, you should target a specific branch as explained below:
+
+* `master` – development branch of Akka 2.4.x
+* `release-2.3` – maintanance branch of Akka 2.3.x
+* `release 2.3-dev` – development branch of Akka Streams and HTTP (only)
+
 ## General Workflow
 
 This is the process for committing code into master. There are of course exceptions to these rules, for example minor changes to comments and documentation, fixing a broken build etc.