Drawing inspiration from longitudinal-experimental studies of youth violence and intervention in the global North, this study was designed as an ambitious two-site, large-n (n=700), longitudinal (3 waves over 24 months) quasi-experimental panel study to explore pathways to violent behaviour and violence-potential along with possible effects of a sport-based life skills programme among young men and boys. Fieldwork challenges led to a revision of the panel sampling and programming setbacks forced the closure of the second site. Lessons drawn from field research and youth-violence intervention in the urban South African context thus form an important component of the 'lived experience' of this study. These adjustments led to a revised quasi-experimental comparison group design which followed 3181 male subjects in Khayelitsha, 12-23 years-old, over a 12 month period. A unique violence-potential 'scorecard' (comprised of four sub-scales: attitudes towards gang associations, attitudes towards the use of instrumental violence, deviant peer associations, and self-reported fighting) was developed and tested through confirmatory factor analysis and correlation with self-reported violent behaviours and an external assessment (from the primary maternal caregiver). The resulting 'Violence Propensity Score' serves as the primary dependent variable in quantitative analyses.