Double houses, monastic communities in which men and women lived, worked and prayed together, are a long-lived and widespread component of the complex jigsaw of medieval monasticism. However, there has never been an English-language monograph on the double house; in fact, there has been no substantial study in any language since 1928. The neglect of double houses is not due to a lack of evidence, but due to a lack of consensus about what to do with this material, which conflicts with current assumptions about gender and monasticism in medieval society. By comparing three manifestations of the double house in England, in the Anglo-Saxon, central and late medieval periods, this book provides a much-needed synthesis of existing studies and a fresh analysis of well-known and lesser-known sources, which prompts us to re-evaluate much of what we think we know about medieval monasticism.