Do emotions happen inside separate hearts and minds, or do they operate across the spaces between individuals? This book focuses on how emotions affect other people by changing their orientation to what happens in the social world. It provides the first sustained attempt to bring together literature on emotion's social effects in dyads and groups, and on how people regulate their emotions in order to exploit these effects in their home and work lives. The chapters present state-of-the-art reviews of topics such as emotion contagion, social appraisal and emotional labour. The book then develops an innovative and integrative approach to the social psychology of emotion based on the idea of relation alignment. The implications not only stretch beyond face-to-face interactions into the wider interpersonal, institutional and cultural environment, but also penetrate the supposed depths of personal experience, making us rethink some of our strongly held presuppositions about how emotions work.