Hildegard of Bingen’s reputation for expertise in medicine was established not during her lifetime but after her death, with the compilation of Physica and Cause et cure by her secretaries and nuns at Rupertsberg. These works arranged and supplemented materials collected and composed by Hildegard. While described by early witnesses as works on medicine, they are not entirely typical of twelfth-century medical writing. Physica is an encyclopedia of the natural world, and Cause et cure an extended meditation on the consequences and remedies for the fall of the human race. Yet both works reveal Hildegard’s familiarity with current scientific and medical theory, as well as principles of secular healing practice. As her medieval readers affirmed, her visionary message was fully compatible with, and amplified in significance by, medical teachings based on Greco-Roman sources. This chapter explores this convergence of spiritual meaning and medical erudition in both works and examines the reception of Hildegard as a ‘medical writer’ in the later Middle Ages and early modern periods, and the ways in which this identity has been used by humanistic and alternative medical movements.