The extent to which classical theories about, and practices of, medical knowledge have shaped and continue to define medicine today is remarkable: but not always widely appreciated. Caroline Petit here offers a concise yet comprehensive account of medicine in antiquity which explores precisely that fascinating legacy. Discussing topics such as medical ethics, diagnostic explanations of illness and disease, matters of sex and gender, the ancient division between body and soul, interpretations of madness and melancholia, and methods of medical teaching and dissemination, the author draws fascinating parallels between the ancient, early modern and modern periods. We learn, positively, that the ancient medical thinking of Galen, Hippocrates and Soranos of Ephesus nourished the thought of some of the greatest physicians in history; but also that, negatively, modern medical thinkers sometimes misused ancient texts in pursuit of their own social and political agendas - a recurring problem in the history of medicine. Discussing a variety of ancient texts, from the Hippocratic era to the late Roman Empire, and examining contested literary evidence and interpretations, Petit skilfully traces the trajectory of medical practice from its magical and religious origins to a rational science of pathology, physiology, surgery and anatomy.