Ethical self-formation and epistemic virtues have been a focus of attention in the history of science for over three decades, and yet, despite some important early contributions, anthropologists of science have only recently started to pay more sustained and explicit attention to the ethical. This chapter argues that anthropologists of science could benefit from taking a closer and more systematic look at recent developments in the anthropology of ethics. Conversely it suggests that anthropologists of ethics might gain from a closer consideration of some of the specificities of Euro-American science as an (internally and externally contested, multiple, and perhaps in part fictitious) ethical tradition. The first half of the chapter explores the rather fitful genealogy of an interest in the ethical in the history, sociology, and anthropology of science, and points to some of the elements from which the anthropology of science as an anthropology of ethics might be (re)built. The second half of the chapter gives one extended, ethnographically grounded example of what such a (re)building might produce, and suggests some of the ways in which anthropology’s exploration of both science and ethics might benefit.