Given that Thomas a Kempis' Imitation of Christ is one of the most frequently translated and read late medieval books of devotion, it is surprising that there are few studies of the work in English. This book fills the void by offering an explication of Thomas' spiritual theology in the Imitation, while situating him in his late medieval monastic context and as someone familiar with and influenced by the Modern Devotion and the Sisters and Brothers of the Common Life. Thomas' emphasis on grace and his dependence on Augustine of Hippo show, to some extent, that he anticipated theological developments of the Protestant Reformation. At the same time, Thomas' eucharistic spirituality, so central to his overall spiritual theology, is quintessentially medieval. Thomas' vision of the spiritual life was expansive and all-inclusive, rich and accessible for both the monk and the devout follower and imitator of Jesus Christ who lived in the world. Thomas' spirituality is for everyone, a synthesis of Christian thought that steers away from the late medieval Scholastic theologies of the university towards a monastic theology and spirituality for anyone who desires to follow Jesus Christ devoutly. His vision remains relevant for all twenty-first-century Christian believers.