There is a need to recognise that gangs are a form of community with accompanying norms, values, processes and practices internal to those communities. Any behaviour change efforts with members of these groups would benefit from being “gang-informed”. However, a workable theory of gangs that informs about function, susceptibility to join, structure (and variations), processes of entry and exit, and outcome issues has yet to developed beyond general theories of crime and desistance. Strategic interventions that are informed by gang cultures – in addition to theories of crime and desistance – are suggested as a constructive area of further research.