How can the Body and Blood of Christ, without ever leaving heaven, come to be really present on eucharistic altars where the bread and wine still seem to be? Marilyn McCord Adams examines how this question and its answer ("transubstantiation") engaged thirteenth and fourteenth century philosophical theologians. There are few books that are as careful in its detail and as cosmic in its scope as Adams's Some Later Medieval Theories of the Eucharist: Thomas Aquinas, Giles of Rome, Duns Scotus, and William Ockham. I heartily recommend it to anyone interested in understanding the nature of Christ's presence among us.