diff --git a/fsl/version.py b/fsl/version.py
index 7800f2cd3c93a57eb1a5811dc620c178b748124f..3c7fd1891a28f4be901d99ef0a298db81b20f9fd 100644
--- a/fsl/version.py
+++ b/fsl/version.py
@@ -41,7 +41,7 @@ import            re
 import            string
 
 
-__version__ = '1.6.5'
+__version__ = '1.6.6'
 """Current version number, as a string. """