The study of liturgical reform is usually undertaken through a close examination of liturgical texts. In order to consider the impact of reform on the worship life of Christians, Katharine Mahon takes a wider view of liturgy by considering the worship practices of Christian churches beyond what appears in the rites themselves. Looking at how Christians were taught how to pray and instructed in liturgical and sacramental participation, Mahon explores the late medieval patterns of Christian ritual formation and the transformation of these patterns in the sixteenth-century reforms of Martin Luther, Thomas Cranmer, and Roman Catholic leaders. She uses the Lord’s Prayer—the backbone of medieval lay catechesis, liturgical participation, and private prayer—to paint a panorama of medieval ritual formation integrated into the life of the church in the fourteenth and fifteenth centuries. She then follows the disintegration and reconstruction of that system of formation through the changing functions of the Lord’s Prayer in the official reforms of catechesis, liturgy, and prayer in the sixteenth-century.