The liberal vision of world politics seemed to emerge triumphant in the aftermath of the Cold War, but doubts have since grown about its superiority and universal appeal. This book rises to its defense, providing a comprehensive restatement of liberalism's intellectual foundations and historical accomplishments. Somewhat awkwardly, the book combines two distinct efforts. One is to make the case for liberalism -- and "the liberal project" -- as the most successful way of organizing the modern world, and the result is a coherent and even inspiring rendering of liberal ideas as they have evolved and spread. The other is to recount the various international human rights treaties and agreements that have been signed in the last half century. This encyclopedic effort shows the impressiveness of the postwar human rights revolution, but it is less successful in illuminating the dilemmas and challenges that confront the liberal internationalist agenda. The authors also reflect thoughtfully on the uneasy embrace of liberalism in non-Western societies. Ultimately, it is liberalism's commitment to tolerance and to the inherent dignity of humans that can make liberalism universally relevant in a world with few, if any, grand ideological rivals.