Carl Schmittâ€™s magnum opus, Constitutional Theory, was originally published in 1928 and has been in print in German ever since. This volume makes Schmittâ€™s masterpiece of comparative constitutionalism available to English-language readers for the first time. Schmitt is considered by many to be one of the most originalâ€”and, because of his collaboration with the Nazi party, controversialâ€”political thinkers of the twentieth century. In Constitutional Theory, Schmitt provides a highly distinctive and provocative interpretation of the Weimar Constitution. At the center of this interpretation lies his famous argument that the legitimacy of a constitution depends on a sovereign decision of the people. In addition to being subject to long-standing debate among legal and political theorists in Western Europe and the United States, this theory of constitution-making as decision has profoundly influenced constitutional theorists and designers in Asia, Latin America, and Eastern Europe. Constitutional Theory is a significant departure from Schmittâ€™s more polemical Weimar-era works not just in terms of its moderate tone. Through a comparative history of constitutional government in Europe and the United States, Schmitt develops an understanding of liberal constitutionalism that makes room for a strong, independent state. This edition includes an introduction by Jeffrey Seitzer and Christopher Thornhill outlining the cultural, intellectual, and political contexts in which Schmitt wrote Constitutional Theory; they point out what is distinctive about the work, examine its reception in the postwar era, and consider its larger theoretical ramifications. This volume also contains extensive editorial notes and a translation of the Weimar Constitution.