The introductory chapter to a book has various purposes: this chapter has three. The first purpose is to ease the reader’s pathway into the subject matter. To achieve this, the chapter provides an overview of the developments that are described throughout the book: broadly what the information is, where it is and the approach taken to it. The second purpose is to set the context of the developments which are described, and this discussion is integrated with material designed to fulfil the third purpose. The third purpose is based on the premise that we construct our own knowledge and that our understandings and progression in further learning are based on that personal knowledge. On this basis, the structure of a writer’s understandings is very relevant to the material that appears in a book.