The last few years have been a fruitful period for the study of children in early Christianity, with numerous books and articles having been published. The book by Horn and Martens is a valuable contribution to this area of research. It covers some of the same field as earlier works, but also supplements them in important ways and widens the field in new directions. The book deals with a number of issues central to the study of ancient childhood. After an introductory chapter with methodological reflections on the concept of ‘child’ and a presentation of the phases of childhood (pagan, Jewish and Christian), Horn and Martens focus on the metaphorical use of ‘child’ within early Christianity, by calling attention to a shift in emphasis from ‘child of God’ to ‘son/daughter of the church’. In the chapters following, the authors deal with the role of children within the Christian household and the cultural formation that they received, partly through the school ‘system’ (for a minority), partly through being taught a profession at home (for the majority). Considerable space is also given to children's play and activities as part of their daily life and their exercise for adult life. Individual chapters deal extensively with matters of great importance for children in antiquity in general, and also for Christian children. Their risk of being exposed to various kinds of violence is discussed at length – attention is not least paid to the situation of slave children. The authors also present the place of children within early Christian worship, with focus on (infant) baptism but also on children's participation in the eucharist and their function as lectors. The final main chapter, before a brief summarising chapter, is devoted to children and asceticism, and the problems and potentials this option of living represented for them. An important point for Horn and Martens is that the introduction and spread of Christianity led to a general improvement in the living conditions of children, with children to a higher degree than earlier being valued as humans and individuals. Although some scholars will be more reserved on this, the authors argue in balanced and nuanced ways in favour of their view. The broad geographical and chronological span of the sources utilised serves to give a helpful overview of the field of study, but occasionally also leads to superficial and fragmentary treatment of some sources. The book is particularly valuable for its sensitivity to how a number of factors would affect children's lives (such as gender, ethnicity, age level, social status and social class), its conscious and occasionally innovative uncovering of children's – often hidden – presence in the sources (also in the biblical writings), and its use of a broad spectrum of sources, not least of apocryphal works and writings from various branches of eastern Christianity. Detailed footnotes, an extensive bibliography and thorough indexes also add to the value of the book, as do the several suggestions on areas in need of further study.