No one has written more insightfully on the promises and perils of human agency than Gary Watson, who has spent a career thinking about issues such as moral responsibility, blame, free will, weakness of will, addiction, and psychopathy. The chapters of this volume pay tribute to Watson’s work by taking up and extending themes from his pioneering essays. Themes covered include:: compatibilist views of freedom and moral responsibility, the distinction between attributability and accountability, the responsibility of psychopaths, the nature of blame and its relationship to morality, the relevance of addiction to responsibility, the continuing influence of P. F. Strawson’s work, the connection between criminal and moral responsibility, the philosophical development of Gary Watson and the ways Watson’s views have changed over time. Contributors include: Michael McKenna, Susan Wolf, Pamela Hieronymi, R. Jay Wallace, Michael Smith, T. M. Scanlon, Jeanette Kennett, Antony Duff, Gideon Yaffe, Gary Watson, Sarah Buss, Neal Tognazzini, and D. Justin Coates.