While it is clear that youth violence poses a serious threat to the health and well-being of the young people in the UK, and the population as a whole, it is unclear what strategies are effective in reducing violent crime among young people. Some initiatives have followed a 'public health approach' which attempt to address societal and attitudinal aspects and generally implies prevention of disease in the population. Many public health interventions are introduced 'upstream' of the onset of disease, and as such many are delivered by non-medical professionals. Public health interventions for youth violence prevention include early interventions with at-risk youth, for example - contact and interaction with an influential peer or positive role model that might affect a change in attitudes and behaviours towards violence. This individual might be a 'peer' (of similar age and/or background), a 'mentor' (someone with more experience, skills and abilities), or a 'peer mediator' who intervenes between youth to prevent retaliation.

This review aimed to provide a comprehensive account of the range of violence prevention programmes for young people (aged up to 25 years) who have either been involved in, or are identified as being at high-risk of violence, and that included contact and interaction with a 'peer mediator', a 'mentor', or an influential 'peer' (peer support).