diff --git a/.travis.yml b/.travis.yml
index f76f7c377..f61020643 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,6 +2,8 @@ language: ruby
 before_install:
 - gem install bundler
 - bundle install
+after_success:
+- script/tag_on_master
 script: bundle exec rake book:build
 deploy:
   provider: releases
diff --git a/script/tag_on_master b/script/tag_on_master
new file mode 100755
index 000000000..ee3382e5d
--- /dev/null
+++ b/script/tag_on_master
@@ -0,0 +1,18 @@
+#!/bin/bash
+
+# This is for running on Travis. It automatically tags any merge to Master as a release in the 2.1.x series.
+if [[ $TRAVIS_PULL_REQUEST != 'false' || "$TRAVIS_BRANCH" != 'master' ]]; then
+  # Don't run on pull requests
+  echo 'This only runs on a merge to master.'
+  exit 0
+fi
+
+# Compute the next tag number
+LASTPATCH=$(git describe --tags | cut -d- -f1 | cut -d. -f3)
+PATCH=$(($LASTPATCH+1))
+echo $PATCH
+
+# Create a tag
+curl -H "Authorization: token ${api-key}" \
+     -X "{\"ref\": \"refs/tags/2.1.$PATCH\", \"sha\": \"$TRAVIS_COMMIT\"}" \
+     https://api.github.com/repos/progit/progit2/git/refs