This volume brings together a broad range of Foreign Affairs content to commemorate the twentieth anniversary of Samuel Huntington’s classic article “The Clash of Civilizations?” Huntington’s essay argued that culture, rather than ideology or geopolitics, would be the driving source of international conflict in the post-Cold War era. It struck a nerve because it raised important and uncomfortable subjects in direct and powerful ways. Two decades on, the jury is still hung, with critics and defenders passionately arguing the piece’s merits and demerits, agreeing only on its enduring significance both as a marker of its times and a theoretical perspective that demands serious engagement. We believe that readers should make up their own minds about how well his argument does and doesn’t hold up. So we’ve pulled together the original article; a broad range of responses from prominent commentators; Huntington’s response to his critics; a recent retrospective analysis by Richard Betts; eulogies of Huntington from Stephen Peter Rosen, Eliot Cohen, Zbigniew Brzezinski, and Henry Rosovsky; and a video of a celebration of Huntington’s career featuring reminiscences from some of his students, including Cohen, Francis Fukuyama, and Fareed Zakaria. An introduction by Foreign Affairs Editor Gideon Rose sets the stage for the debates that follow.