Despite the importance of commitment in moral and political philosophy, there has hitherto been little extended analysis of it. Marcel Lieberman examines the conditions under which commitment is possible, and offers at the same time an indirect argument for moral realism. His ambitious study addresses questions that are of great interest to analytic philosophers but also makes many connections with continental philosophy and with folk psychology, sociology and cognitive science. It will be seen as a novel and distinctive intervention in the debate about moral realism.