diff --git a/CHANGES.rst b/CHANGES.rst
index c894a0a..f8fff6a 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,6 +1,10 @@
 CHANGES
 =======
 
+master (unreleased)
+-------------------
+
+
 2.5 (2016-04-18)
 ----------------
 
diff --git a/model_utils/__init__.py b/model_utils/__init__.py
index 5afa1a5..612fb9f 100644
--- a/model_utils/__init__.py
+++ b/model_utils/__init__.py
@@ -1,4 +1,4 @@
 from .choices import Choices
 from .tracker import FieldTracker, ModelTracker
 
-__version__ = '2.5'
+__version__ = '2.5.1a1'