Many emotions are not only socially constructed, but are constituted in relation to different kinds of social collectives. Theories of collective emotions address the collective constitution of emotions and their social consequences in different ways. Emotions can be collective because of group membership or the collective properties of mental states underlying them (e.g., collective intentions or shared concerns). They can also be collective because they are simultaneously experienced by many individuals via processes of emotional contagion as well as through culture and social norms. Collective emotions can promote social solidarity but also fuel conflict and exclusion.