diff --git a/README.rst b/README.rst
index 4edc9d4..6513925 100644
--- a/README.rst
+++ b/README.rst
@@ -73,6 +73,9 @@ Changelog
 dev
 ```
 
+0.4.0
+`````
+
 * Support sending json for selected slack methods.
 
 0.3.5
diff --git a/slack/__version__.py b/slack/__version__.py
index 74e4010..13c6249 100644
--- a/slack/__version__.py
+++ b/slack/__version__.py
@@ -1,3 +1,3 @@
 # Version information
 
-__version__ = '0.3.5'
+__version__ = '0.4.0'