In this lecture the 4-step model is revisited again; this time the focus is on the background of the 4-step model. In the first part of the lecture, the concept behind the model is discussed and its individual components are reviewed to give a better idea on when to use what.

Then, the future of the 4-step model is discussed. Also, the model is placed next to other models in order to compare them. Lastly, steps for extending the 4-step model to make it applicable for other topics are discussed.