In this welcome new book Marcia L. Colish offers the only monograph-length study of the patriarch treatises of Ambrose of Milan (c. 340-397), in which he develops, for the first time in the patristic period, an ethics for the laity. Ambrose the ethicist has been viewed primarily as the author of advice to those with special callings in the church, such as priests, widows, and consecrated virgins. His views have been characterized as advocating asceticism and promoting a Platonic view of human nature, in which the body is a moral problem. Ambrose's patriarch treatises, argues Colish, are instead aimed at lay people who did not have special callings in the church, but who led active lives in the world as spouses, parents, heads of households, professionals, and citizens. These treatises reveal a different side of Ambrose and show that he developed an ethics of moderation based on an Aristotelian and Stoic anthropology, which he modified in the light of biblical ethics and St. Paul's view of human nature.