Ancient Greek thought saw the birth, in Western philosophy, of the study now known as moral psychology. In its broadest sense, moral psychology encompasses the study of those aspects of human psychology relevant to our moral lives--desire, emotion, ethical knowledge, practical moral reasoning, and moral imagination--and their role in apprehending or responding to sources of value. This volume draws together contributions from leading international scholars in ancient philosophy, exploring central issues in the moral psychology of Plato, Aristotle, and the Hellenistic schools. Through a series of chapters and responses, these contributions challenge and develop interpretations of ancient views on topics from Socratic intellectualism to the nature of appetitive desires and their relation to goodness, from the role of pleasure and pain in virtue, to our capacities for memory, anticipation and choice and their role in practical action, to the question of the sufficiency or otherwise of the virtues for a flourishing human life.