diff --git a/CHANGES.rst b/CHANGES.rst
index 7e98941..06b0737 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -2,6 +2,12 @@
  Changelog
 ===========
 
+4.2 (unreleased)
+================
+
+- Nothing changed yet.
+
+
 4.1.2 (2018-10-10)
 ==================
 
diff --git a/setup.py b/setup.py
index 42cd7af..fb35212 100644
--- a/setup.py
+++ b/setup.py
@@ -27,7 +27,7 @@ def read(*rnames):
 
 setup(
     name="zope.sequencesort",
-    version='4.1.2',
+    version='4.2.dev0',
     author='Zope Foundation and Contributors',
     author_email='zope-dev@zope.org',
     description='Sequence Sorting',