diff --git a/fsl/version.py b/fsl/version.py
index 00759529c26da5a7a75ec73bfcd5f8b7fb01d353..bf35a0ffd80b55089a608cf56415b681469047ae 100644
--- a/fsl/version.py
+++ b/fsl/version.py
@@ -41,7 +41,7 @@ import            re
 import            string
 
 
-__version__ = '1.3.0.dev'
+__version__ = '1.4.0.dev'
 """Current version number, as a string. """