diff --git a/README_DEVELOPER.md b/README_DEVELOPER.md
index ae3f12a0e84..14aaa4deb9b 100644
--- a/README_DEVELOPER.md
+++ b/README_DEVELOPER.md
@@ -184,6 +184,30 @@ installed using [Bundler](http://gembundler.com/)
     Using bundler (1.1.5)
     Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed.
 
+# Running Tests #
+
+Puppet Labs projects use a common convention of using Rake to run unit tests.
+The tests can be run with the following rake task:
+
+    rake spec
+    # Or if using Bundler
+    bundle exec rake spec
+
+This allows the Rakefile to set up the environment beforehand if needed. This
+method is how the unit tests are run in [Jenkins](https://jenkins.puppetlabs.com).
+
+Under the hood Puppet's tests use `rspec`.  To run all of them, you can directly
+use 'rspec':
+
+    rspec
+    # Or if using Bundler
+    bundle exec rspec
+
+To run a single file's worth of tests (much faster!), give the filename, and use
+the nested format to see the descriptions:
+
+    rspec spec/unit/ssl/host_spec.rb --format nested
+
 # UTF-8 Handling #
 
 As Ruby 1.9 becomes more commonly used with Puppet, developers should be aware