diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7aa51ac9f..8098d2edb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,12 @@
 # Change Log
 All notable changes to this project will be documented in this file.
 
+## [5.1.0] - 2017-08-30 ##
+### Added
+- Pull #338: Allow the `__str__` method for the `Mail` object return an `String` instead of a `NoneType`
+- Solves #292: The `__str__` method of the `Mail` class, doesn't actually return anything
+- Big thanks to [belfazt](https://github.com/belfazt) for the pull request!
+
 ## [5.0.1] - 2017-08-29
 ### Fix
 - Pull #337, fixes issue #366
diff --git a/docker/README.md b/docker/README.md
index 438695f41..a3561fbc0 100644
--- a/docker/README.md
+++ b/docker/README.md
@@ -1,5 +1,6 @@
 # Supported tags and respective `Dockerfile` links
- - `v5.0.1`, `latest` [(Dockerfile)](https://github.com/sendgrid/sendgrid-python/blob/master/docker/Dockerfile)
+ - `v5.1.0`, `latest` [(Dockerfile)](https://github.com/sendgrid/sendgrid-python/blob/master/docker/Dockerfile)
+ - `v5.0.1`
  - `v5.0.0`
  - `v4.2.1`
  - `v4.2.0`
diff --git a/sendgrid/version.py b/sendgrid/version.py
index 9fced9f38..a230e21cd 100644
--- a/sendgrid/version.py
+++ b/sendgrid/version.py
@@ -1,2 +1,2 @@
-version_info = (5, 0, 1)
+version_info = (5, 1, 0)
 __version__ = '.'.join(str(v) for v in version_info)