This chapter is a synthesis of the views on theorizing teaching put forward in Chaps. 2, 3, 4, 5, 6, 7, 8 and 9 and those that emerged from the Delphi study in Chap. 10. In considering these views, we discuss a number of questions: Do theories of teaching exist? If they do, how are they defined, what purpose do they serve, and what attributes do they have? How should theories be generated, and is it possible to develop a comprehensive theory of teaching? What role does content specificity and context sensitivity have in the generation of such theories? What role can teachers play in this process and how can theories of teaching inform practice? The chapter considers how and why the contributors’ views on these questions agreed or differed, and identifies pathways to resolving differences. The exercise demonstrates the importance of providing the research community with opportunities for focused and systematic discussion. As the capstone of this book, the chapter also proposes ways in which the field of theorizing teaching can be moved forward.