diff --git a/README.md b/README.md
index 9522d40a..d2c04596 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,13 @@
 
 Discord for development/support/play: https://discord.gg/5XuDkje
 
+## Important notice
+
+This is the development branch for factorioClusterio 2.0 which is currently undergoing heavy
+restructuring and refactoring.  Expect plugins and existing installations to frequenltly break when
+using this branch.  If you don't want to be an alpha tester for 2.0 please use the stable
+[1.2.x branch](https://github.com/clusterio/factorioClusterio/tree/1.2.x).
+
 ### Ways to support me/the project:
 
 * Contribute with code/documentation. Always nice to move the project forward