a 3-year collaboration that included a workshop at the University of Queensland, an ISA roundtable, and, mostly, countless rounds of mutual feedback and adjustments.The Forum is structured around a combination of article-length essays and commentaries. The editors first offer a theoretically oriented survey of the state of current research on the topic: a one-stop location for readers who want to know about emotions and world politics. Then follow essays by the two pioneers in this field: Jonathan Mercer and Neta Crawford. Both have made path-breaking early contributions, which have substantially shaped scholarly discussions on the topic. Seven shorter commentaries will then either directly engage the previous texts or take on important additional aspects of emotions and world politics. Contributors have been selected so that they represent a broad spectrum of theoretical and methodological positions. The authors are either specialists on emotions research or experienced scholars who comment on the relevance of the respective insights for the broader theory and practice of international relations.All contributions revolve around one central challenge: to theorize the processes that render individual emotions collective and thus political. This is, however, not to say that the contributors present uniform positions. While agreeing that emotions are political, the contributors divergeat times stronglyon how emotions become so and what consequences are entailed. The Forum is thus primarily a venue for deliberation and critique that aims to encourage further innovative research on this crucial but still largely under-theorized topic.Emotions play an increasingly important role in international relations research. This essay briefly surveys the development of the respective debates and then offers a path forward. The key challenge, we argue, is to theorize the processes through which individual emotions become collective and political. We further suggest that this is done best by exploring insights from two seemingly incompatible scholarly tendencies: macro theoretical approaches that develop generalizable propositions about political emotions and, in contrast, micro approaches that investigate how Forum: Emotions and World Politics 491