This study is the latest of a number of weighty attempts over the last half-century or so to make sense of the controversies over the nature of Christian doctrine that were unleashed by the peace of the Church under Constantine. Traditionally this controversy has been seen – as Athanasius, largely followed by the fifth-century Church historians, wanted it to be seen – as the ‘Arian’ controversy and a struggle for Trinitarian orthodoxy. The first of the modern discussions (Simonetti, Hanson) came from more senior scholars, who still countenanced the idea of the ‘Arian controversy’; the more recent studies (Behr, Ayres) from scholars earlier on in their careers, who preferred to think of it differently. Anatolios's contribution falls into the latter category. It is not easy to establish a fresh perspective in such well-trodden territory, but Anatolios succeeds magnificently. After a brief survey of the history of fourth-century Trinitarian controversy, and an even briefer glance at earlier approaches, Anatolios begins his own discussion by, first of all, making clear how much there was in common among all the different participants in the controversy: all accepted the same scriptural canon, sense of an apostolic tradition and the primacy of faith; all accepted the Trinity as the object of their common faith and worship, and agreed, too, that the universe was created out of nothing; in relation to Christ himself, there was much general agreement – he was confessed in worship with various titles such as God, Lord, Logos, Wisdom, Light etc., he pre-existed creation and indeed created it, he was both human and divine, and the Saviour of the world. There were various negative boundaries, too, universally acknowledged: Manichaeism, Gnostic emanationism, belief that Jesus was a mere man and Sabellianism were all disavowed. Within this commonality, Anatolios suggests that there were two, opposed, though in principle complementary, trajectories in formulating the doctrine of the Trinity: one looking for unity of will, the other for unity of being, within the Trinity. There follow brief accounts of representatives of these two trajectories: for unity of will, Arius, Asterius, Eusebius of Caesarea, Eunomius; for unity of being, Alexander of Alexandria, Marcellus, Apollinaris. Then comes the main part of the book, dealing with Athanasius, Gregory of Nyssa and Augustine; the first two are said to represent unity of will, but incorporating some of the concerns of unity of being (so p. 98, but I think what is meant is unity of being, with some accommodation of unity of will; that is certainly what the following chapters suggest), while Augustine represents unity of being, with little concern for willing within the Trinity. This seems to me a largely successful strategy; at any rate, the chapters that follow are based on much learning and are full of insights. In the chapter on Augustine Anatolios wears his learning very lightly, and seems to be beholden to some unstated agenda, but the chapter is full of insight none the less. Anatolios also makes useful references to modern discussions of Trinitarian theology.