Although collective emotions have a long tradition in scientific inquiry, for instance in mass psychology and the sociology of rituals and social movements, their importance for individuals and the social world has never been more obvious than in the past decades. The Arab Spring revolution,the Occupy Wall Street movement, and mass gatherings at music festivals or mega sports events clearly show the impact collective emotions have both in terms of driving conflict and in uniting people. But these examples only show the most obvious and evident forms of collective emotions. Others aremore subtle, although less important: shared moods, emotional atmospheres, and intergroup emotions are part and parcel of our social life. Although these phenomena go hand in hand with any formation of sociality, they are little understood. Moreover, there still is a large gap in our understandingof individual emotions on the one hand and collective emotional phenomena on the other hand.This book presents a comprehensive overview of contemporary theories and research on collective emotions. It spans several disciplines and brings together, for the first time, various strands of inquiry and up-to-date research in the study of collective emotions and related phenomena. In focusing onconceptual, theoretical, and methodological issues in collective emotion research, the volume narrows the gap between the wealth of studies on individual emotions and inquiries into collective emotions. The book catches up with a renewed interest into the collective dimensions of emotions and theirclose relatives, for example emotional climates, atmospheres, communities, and intergroup emotions. This interest is propelled by a more general increase in research on the social and interpersonal aspects of emotion on the one hand, and by trends in philosophy and cognitive science towards refinedconceptual analyses of collective entities and the collective properties of cognition on the other hand. The book includes sections on: Conceptual Perspectives; Collective Emotion in Face-to-Face Interactions; The Social-Relational Dimension of Collective Emotion; The Social Consequences of Collective Emotions; Group-Based and Intergroup Emotion; Rituals, Movements, and Social Organization; andCollective Emotions in Online Social Systems.Including contributions from psychologists, philosophers, sociologists, and neuroscience, this volume is a unique and valuable contribution to the affective sciences literature.