The attempt to regenerate city centres has led to the creation of a 'night-time economy' (NTE) based around alcohol-led entertainment. This has been accompanied by an increase of violence. Using insights from social identity research on collective action, we argue that NTE violence can be viewed as a group-level phenomenon. Twenty focus groups were conducted with participants who socialise together (total number of participants=53). Participants discussed their experiences of the NTE, including violence. A thematic analysis of the transcripts drew out four ways in which NTE violence is discussed in group terms: intergroup violence, intragroup violence, intragroup intervention (escalation) and intragroup intervention (regulation). The analysis reveals that groups can have both negative and positive roles in NTE violence, including regulating fellow group members away from violence. In demonstrating the importance of intragroup regulation of violence in the NTE, we extend social identity research beyond the focus on intergroup crowd violence and reveal the practical potential of harnessing such processes in anti-violence interventions.