diff --git a/CHANGES.rst b/CHANGES.rst
index b348506d0..73052b513 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,5 +1,11 @@
 .. currentmodule:: werkzeug
 
+Version 2.3.9
+-------------
+
+Unreleased
+
+
 Version 2.3.8
 -------------
 
diff --git a/src/werkzeug/__init__.py b/src/werkzeug/__init__.py
index 0a472ae7d..7103d3d42 100644
--- a/src/werkzeug/__init__.py
+++ b/src/werkzeug/__init__.py
@@ -3,4 +3,4 @@
 from .wrappers import Request as Request
 from .wrappers import Response as Response
 
-__version__ = "2.3.8"
+__version__ = "2.3.9.dev"