In this chapter, the authors present the proposal of the questions and the final model which will be applied in the company in order to obtain at the end the result of the maturity level. These questions, as explained in the Chapter 2, came from a mix of project management methods and good practices and from the nature of the pillars of complex projects. The chapter also introduces the questions, explains the pillars in which the questions are split one by one, and finally presents the questions. This is one of the most important chapters in the book because it introduces the proposal to measure maturity in complex projects. The reader can easily perceive by looking over the questions and pillars that this is a different model proposed, which now includes some different pillars such as stakeholders, environment, engineering, and others. The main idea of this chapter is to introduce and explain to the reader the origin of the questions which will be, at the end, the model proposed for the book.