Collective nostalgia is a group-based emotion that reflects a sentimental longing for a time in the past of one’s group (the ingroup) that is perceived to be better than what the ingroup is currently experiencing. Collective nostalgia is particularly likely to occur in times of rapid political and social change perceived as causing discontinuity in a group’s history. By focusing people’s attention on important elements of group identity that need to be preserved, collective nostalgia has the potential to strengthen a sense of collective continuity between group’s past, present, and future. It does so by increasing the likelihood of engagement in constructive (e.g. collective action) and destructive (e.g. rejection of outgroups) group-protective activities. Which of these two avenues prevail depends on the exact elements of group’s past that members feel nostalgic for (i.e. on the content of collective nostalgia).