The empirical analysis sheds new light on how populists’ distinctive conception of a world divided antagonistically between “the people” and “the elites” influences behaviour towards multilateral organizations such as the United Nations and the European Union, and regional or global hegemonic powers like the United States, Germany, Russia, and China. The book also shows how ideas related to identity, ideology, status and emotions, impinge on populists’ conduct vis-à-vis other international actors, and how national and international structures affect the implementation of populist foreign policies in the regional, interregional, and global arenas. The wide geographical diversity and regional representation are also valuable in identifying cultural similarities and differences. Hence, the findings contribute to lively debates on whether populism leads to a gradual “corrective” of transnational trends in contemporary politics or, conversely, to a more radical, structural shift in the liberal international order.