This book asks how ethics can help us to understand the encounter between French colonists and Algerians in the Nineteenth century. It focuses on questions of medicine since the claimed goodness of the French 'civilising mission' depended on the idea that the health of the Algerian people would be improved under imperial rule. In looking at the manner in which such moral claims were constructed and the way in which they operated in practice, Gallois offers one of the first comparative histories of medicine and ethics. The book argues that while the French failure to 'medicalise' Algerian society is well understood, histories of health also need to consider ways in which policies of massacre and extermination were conceived as being morally good, and how the diminution of the Algerian population was countenanced at moments of famine and epidemic disease. It also offers the first accounts of Algerian doctors working in colonial medicine, looking at the manner in which they developed an ethics of resistance to empire.