diff --git a/altair/__init__.py b/altair/__init__.py
index 0bd555e1e..a8c63edd9 100644
--- a/altair/__init__.py
+++ b/altair/__init__.py
@@ -1,4 +1,4 @@
-__version__ = '1.1.0.dev0'
+__version__ = '1.2.0'
 
 from .api import (
     Label,
diff --git a/doc/conf.py b/doc/conf.py
index b8c8204bb..4b697757d 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -70,9 +70,9 @@
 # built documents.
 #
 # The short X.Y version.
-version = '1.0.0'
+version = '1.2.0'
 # The full version, including alpha/beta/rc tags.
-release = '1.0.0'
+release = '1.2.0'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.