diff --git a/flask/__init__.py b/flask/__init__.py
index b170ba5f..196eb033 100644
--- a/flask/__init__.py
+++ b/flask/__init__.py
@@ -10,7 +10,7 @@
     :license: BSD, see LICENSE for more details.
 """
 
-__version__ = '0.9'
+__version__ = '0.10-dev'
 
 # utilities we import from Werkzeug and Jinja2 that are unused
 # in the module but are exported as public interface.
diff --git a/setup.py b/setup.py
index 9b185fc0..1d0761fe 100644
--- a/setup.py
+++ b/setup.py
@@ -77,7 +77,7 @@ class run_audit(Command):
 
 setup(
     name='Flask',
-    version='0.9',
+    version='0.10-dev',
     url='http://github.com/mitsuhiko/flask/',
     license='BSD',
     author='Armin Ronacher',