Quality improvement teams function best when all team members agree to a unifying model to guide their effort. Unfortunately, there are many quality improvement project models to choose from in the literature. And while it seems that they are quite different, all effective models are built on the same conceptual base. In this tutorial, we will explain these basic concepts and then show how to use them to examine and enhance our understanding of some widely used models. We will also discuss the need for these models, describe how teams can learn from projects that followed different models, and provide guidance to organizations that are choosing one.