"The Perfect Servant" reevaluates the place of eunuchs in Byzantium. Kathryn Ringrose uses the modern concept of gender as a social construct to identify eunuchs as a distinct gender and to illustrate how gender was defined in the Byzantine world. At the same time she explores the changing role of the eunuch in Byzantium from 600 to 1100. Accepted for generations as a legitimate and functional part of Byzantine civilization, eunuchs were prominent in both the imperial court and the church. They were distinctive in physical appearance, dress and manner and were considered uniquely suited for important roles in Byzantine life. Transcending conventional notions of male and female, eunuchs also lived outside of normal patterns of procreation and inheritance and were assigned a unique capacity for mediating across social and spiritual boundaries. This allowed them to perform tasks from which prominent men and women were constrained, making them, in essence, perfect servants. Written with precision and meticulously researched, "The Perfect Servant" should immediately take its place as a major study on Byzantium and the history of gender.