diff --git a/README.md b/README.md
index a7a2f4f54..1354d4845 100644
--- a/README.md
+++ b/README.md
@@ -62,6 +62,17 @@ for setup and user guide.
 `haskell-mode` supports GNU Emacs versions 23, 24 and upcoming 25
 (snapshot).
 
+Emacs23 requires an the use of "cl-lib".  cl-lib.el can be found in
+the tests/compat directory.  Copy cl-lib.el to your emacs
+directory, e.g. ~/.emacs.d directory and put
+
+```el
+(add-to-list 'load-path "~/.emacs.d/")
+(require 'cl-lib)
+```
+
+in your .emacs file.
+
 `haskell-mode` is available from [melpa-stable](http://http://stable.melpa.org) (releases) and [melpa](http://melpa.org)
 (git snapshots).