This is a remarkable book on the diplomatic processes surrounding Iran's nuclear program. The focus is on the dynamic relationships between Iran and the six 'world powers' (the five permanent members of the UN Security Council plus India). Following a short introduction, presenting the main argument and the analytical frame, the book devotes one chapter each to Iran's relations with, respectively: the US; the 'EU3' (France, Germany, the United Kingdom); Russia; China; and India. Each of these five substantial chapters presents the history of bilateral relations, examining in great detail the interaction 'before' (2011–12), 'during' (2013–16), and 'after' (2017–2021) the negotiations of the Joint Comprehensive Plan of Action. By widening the scope to include not only those directly involved in the talks – the US and Europe – Keynoush gives us incomparable insights into a complex web of strategic ambitions, contradictory aims, and mutual misunderstandings. In this account, the negotiations over Iran's nuclear program also become a prism for understanding a period in history when unilateralism was systematically challenged by aspiring world powers as well as emerging middle powers. The repercussions, for nuclear proliferation, for economic interconnectedness, for regional (in-)security in the Gulf, are insurmountable. For Iran, argues Keynoush, the nuclear program – and the related negotiations – provided a vehicle for building middle power status, strengthening its regional influence, and challenging what it saw as an unjust global order. While successful, at least in part, Iran met unexpected international pressure and was unable to convert its piecemeal victories into sustainable security. This book deserves to become a prime reference.