diff --git a/CHANGES.rst b/CHANGES.rst
index e91547f..7fa6013 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,6 +1,11 @@
 ``persistent`` Changelog
 ========================
 
+4.2.2 (unreleased)
+------------------
+
+- TBD
+
 4.2.1 (2016-05-26)
 ------------------
 
diff --git a/setup.py b/setup.py
index b9b4bf9..e12517a 100644
--- a/setup.py
+++ b/setup.py
@@ -12,7 +12,7 @@
 #
 ##############################################################################
 
-__version__ = '4.2.1'
+__version__ = '4.2.2.dev0'
 
 import os
 import platform