A total of 3,535 trauma cases were enumerated in Johannesburg-Soweto between 1989 and 1990 in the course of 271 hospital ward rounds and 43 casualty watches. The overall trauma incidence was 2,886 new cases per annum per 100,000 population, rising to 19,872 for coloured males aged 20 - 24 years and to 8,761 for black males aged 20 - 24 years. Overall the male/female ratio was 2.9 rising to 6 or more in adolescence (15 - 19) for blacks and coloureds. There were some 156 new resident cases of trauma daily; half these were victims of interpersonal violence, and coloureds constituted 22% of this group, although forming only 8% of the denominator population. With regards to cause, most trauma among blacks and coloureds arose from interpersonal violence and significantly less from transport accidents. Among blacks injured in transport accidents (the majority of which involved motor vehicles) most were pedestrians, whereas most whites injured in such accidents were occupants of vehicles. For all groups trauma was most likely to be incurred 'in the street' although for white and coloured women the home was most dangerous. The implications of these and related findings for treatment and prevention and briefly reviewed.