diff --git a/CHANGES.rst b/CHANGES.rst
index adaaa08..8f91b20 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -2,6 +2,12 @@
  Changes
 =========
 
+6.1 (unreleased)
+================
+
+- Nothing changed yet.
+
+
 6.0 (2023-07-12)
 ================
 
diff --git a/setup.py b/setup.py
index b32944f..5f51b00 100644
--- a/setup.py
+++ b/setup.py
@@ -37,7 +37,7 @@ def read(*rnames):
 
 setup(
     name='zope.tales',
-    version='6.0',
+    version='6.1.dev0',
     author='Zope Foundation and Contributors',
     author_email='zope-dev@zope.dev',
     description='Zope Template Application Language Expression Syntax '