Deliberative democracy has been the main game in contemporary political theory for two decades and has grown enormously in size and importance in political science and many other disciplines. The Oxford Handbook of Deliberative Democracy not only takes stock of deliberative democracy as a research field, but also explore and create links with philosophy, various research programmes in the social sciences and law, as well as policy practice around the globe. It provides a concise history of deliberative ideals in political thought while also discussing their philosophical origins. The Handbook locates deliberation in a political system with different spaces, publics, and venues, including parliament and courts but also governance networks, protests, mini-publics, old and new media, and everyday talk. It documents the intersections of deliberative ideals with contemporary political theory, involving epistemology, representation, constitutionalism, justice, and multiculturalism. It also explores the intersections of deliberative democracy with major research fields in the social sciences and law, including social and rational choice theory, communications, psychology, sociology, international relations, framing approaches, policy analysis, planning, democratization, and methodology. . The volume engages with practical applications, mapping deliberation as a reform movement and as a device for conflict resolution, documenting the practice and study of deliberative democracy around the world, in Asia, Latin America, Africa, Europe and global governance. It provides reflections on the field by pioneering thinkers such as Jurgen Habermas, Amy Gutmann, Dennis Thompson, and Robert Goodin.