What is a person? This fundamental question is a perennial concern of philosophers and theologians. But, Christian Smith here argues, it also lies at the center of the social scientist's quest to interpret and explain social life. In this ambitious book, Smith presents a new model for social theory that does justice to the best of our humanistic visions of people, life, and society. Finding much current thinking on personhood to be confusing or misleading, Smith finds inspiration in critical realism and personalism. Drawing on these ideas, he constructs a theory of personhood that forges a middle path between the extremes of positivist science and relativism. Smith then builds on the work of Pierre Bourdieu, Anthony Giddens, and William Sewell to demonstrate the importance of personhood to our understanding of social structures. From there he broadens his scope to consider how we can know what is good in personal and social life and what sociology can tell us about human rights and dignity. Innovative, critical, and constructive, What Is a Person? offers an inspiring vision of a social science committed to pursuing causal explanations, interpretive understanding, and general knowledge in the service of truth and the moral good.