diff --git a/javascript/running-es6-specs-with-mocha.md b/javascript/running-es6-specs-with-mocha.md
index e1c7d8e..0b229e1 100644
--- a/javascript/running-es6-specs-with-mocha.md
+++ b/javascript/running-es6-specs-with-mocha.md
@@ -13,4 +13,7 @@ $ mocha --compilers js:babel-core/register path/to/specs/*.spec.js
 If you already have a test command specified in your `package.json` file,
 you can update it with the `--compile` portion of the above command.
 
+This all assumes you've already setup your project with Babel and Babel
+presets.
+
 [source](http://jamesknelson.com/testing-in-es6-with-mocha-and-babel-6/)