diff --git a/Changelog.rst b/Changelog.rst
index 9fed6637..97494350 100644
--- a/Changelog.rst
+++ b/Changelog.rst
@@ -3,6 +3,9 @@
 Changelog
 =========
 
+5.1.0 (dev)
+-----------
+
 5.0.0 (2016-10-19)
 ------------------
 
diff --git a/docs/conf.py b/docs/conf.py
index 31378e79..aa29f2dd 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -52,9 +52,9 @@ copyright = u'2013, Honza Král'
 
 
 # The short X.Y version.
-version = '5.0.0'
+version = '5.1.0'
 # The full version, including alpha/beta/rc tags.
-release = '5.0.0'
+release = '5.1.0-dev'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
diff --git a/elasticsearch/__init__.py b/elasticsearch/__init__.py
index 866601ad..8136feab 100644
--- a/elasticsearch/__init__.py
+++ b/elasticsearch/__init__.py
@@ -1,6 +1,6 @@
 from __future__ import absolute_import
 
-VERSION = (5, 0, 0)
+VERSION = (5, 1, 0, 'dev')
 __version__ = VERSION
 __versionstr__ = '.'.join(map(str, VERSION))
 
diff --git a/setup.py b/setup.py
index 2c68f8b0..5d44886c 100644
--- a/setup.py
+++ b/setup.py
@@ -3,7 +3,7 @@ from os.path import join, dirname
 from setuptools import setup, find_packages
 import sys
 
-VERSION = (5, 0, 0)
+VERSION = (5, 1, 0, 'dev')
 __version__ = VERSION
 __versionstr__ = '.'.join(map(str, VERSION))