Objective. To identify risky sexual behaviours and demographic factors that place high-school pupils at risk of HIV and AIDS. Methods. A cross-sectional study was undertaken to explore factors influencing the sexual behaviour of high-school pupils (mean age 15.4 years; SD 1.11). Structured self-reported questionnaires were completed by all grade 10 pupils (N=805) at all the Wentworth, Durban, public high schools.