This eminently thorough monograph provides a fine account of the cosmology of St Maximus, rightly christening it Christocentric yet remaining alive to its Trinitarian dimensions. We are treated to a detailed discussion of the philosophical genealogy of Maximus' system showing both continuities and divergences from various classical conceptions of exemplarism – the world, that is, as somehow rooted in and reflecting the divine. Tollefsen offers a searching account of God's activity or energeia and also delves into the nature of cosmic and human participation in God, commendably attempting a precise definition of such participation. This book does a great service in deepening and expanding our understanding of Maximus' well-known doctrine of the logoi. These principles of creation are the means by which the Logos manifests and incarnates himself throughout the intelligible and sensible cosmos in accordance with Maximus' own dictum: ‘Always and all God's Word, who is God, wills to effect the mystery of his own embodiment’ (Ambigua 7, PG xci.1084CD). One might have hoped for more on the theme of wisdom although there is, thankfully, much more on this subject than the single reference in the rather spare index might have suggested. Tollefsen is perhaps a little too sanguine in supposing that it is possible to extract a ‘system’ from Maximus' wide and diffuse œuvre although there is no doubt that the Confessor's cosmological vision is both coherent and broadly consistent. Tollefsen admits that he has not been able to make allowance for development in Maximus' thinking over time and it must be said that a stronger historical dimension might have helped nuance the overall picture. The drawbacks of a systematic or synthetic approach may be witnessed in the treatment of the gnomic will – arguably the thorniest and most impenetrable of Maximus' doctrines. Tollefsen gives us a single definition of the gnomic will somewhat belying the considerable development in and complications surrounding Maximus' own use and construal of a term which he himself admitted had no less than twenty-eight different meanings in Scripture and the Fathers. Readers with interests in later Byzantine and Orthodox theology will be fascinated by the presentation of Maximus' teaching on divine essence and energies as being firmly set on a Palamite trajectory. This is a careful and illuminating study of arguably the greatest Byzantine theologian.