Transforming NATO: New Allies, Missions, and Capabilities, by Ivan Dinev Ivanov, examines the three dimensions of NATO’s transformation since the end of the Cold War: the addition of a dozen new allies; the undertaking of new missions such as peacekeeping, crisis response, and stabilization; and the development of new capabilities to implement these missions. The book explains these processes through two mutually reinforcing frameworks: club goods theory and the concept of complementarities. NATO can be viewed as a diverse, heterogeneous club of nations providing collective defense to its members, who, in turn, combine their military resources in a way that enables them to optimize the Alliance’s capabilities needed for overseas operations. Transforming NATO makes a number of theoretical contributions. First, it offers new insights into understanding how heterogeneous clubs operate. Second, it introduces a novel concept, that of complementarities. Finally, it re-evaluates the relevance of club goods theory as a framework for studying contemporary international security. These conceptual foundations apply to areas well beyond NATO. They provide useful insights into understanding the operation of transatlantic relations, alliance politics, and a broader set of international coalitions and partnerships. This update in April 2013 covers new developments related to NATO’s transformation after this book was originally published: http://homepages.uc.edu/~ivanovid/pdfs/book_update.pdf