diff --git a/CHANGES b/CHANGES
index e13ae41be..565eefec5 100644
--- a/CHANGES
+++ b/CHANGES
@@ -10,6 +10,7 @@ Version 6.7
 
 - Make `click.progressbar` work with `codecs.open` files. See #637.
 - Fix bug in bash completion with nested subcommands. See #639.
+- Fix test runner not saving caller env correctly. See #644.
 
 Version 6.6
 -----------