diff --git a/README.md b/README.md
index 6a06a0f..d868700 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,10 @@
+# DISCLAIMER
+
+This repository is in early experimental stage. As soon as it is mature,
+this disclaimer will be removed and the project will be publicly announced
+through the mailing list. Until then, you are invited to try this and report
+your experiences, but you might experience some problems.
+
 # Dune Spack repository
 ## Installation
 Clone spack git