While Turkey has been traditionally deeply entrenched in the Western alliance, the country lately had a significant deterioration of its relationship with the West. This chapter first outlines the puzzle that this book addresses: How and why does Turkey increasingly go its own way within the Western alliance and grow further apart from its traditional Western allies? It then places Turkey’s relations with the West in a historical perspective, by focusing first on the history of Turkey–EU relations and then on Turkey–NATO–USA relations. It discusses the research methodology used in addressing these questions, especially the author’s unique fieldwork and semi-structured elite interviews with over 200 government officials, diplomats, EU, NATO, and OSCE officials, academics, non-governmental organization officials, and journalists in Turkey, Serbia, Bosnia and Herzegovina, Cyprus, the United Kingdom, Germany, and the United States. It offers a justification for the selection of cases examined throughout the book and concludes by discussing the outline of the book.