Dependency Injection, and Dependency Injection Containers are some of the bigger buzzwords in PHP frameworks in the past few years. I'll be reviewing what dependency injection is at a high-level. Then we'll look at why CakePHP how dependency injection works in CakePHP without a container. In 4.2 we'll be adding an injection container for use in applications. I'd like to cover how that integration will work and give some guidelines/recommendations for how to use a Dependency Injection container in your application.