The goal of this manuscript is to advance HIV risk behavior prevention efforts for South African adolescent girls by identifying distinct trajectory patterns across multiple behavioral domains for adolescent and young adults. We draw from a sample of N = 1070 adolescent girls from South Africa who were between the ages of 13-15 at baseline. Participants were followed across 6 waves of data collection between 2011 and 2019. We focus on predicting trajectories between ages 15 and 21. All participants were HIV negative and had not experienced sexual debut at baseline. We examine group-based multi-variable trajectories across several known HIV risk behaviors: earlier age of sexual debut, engaging in unprotected sex, engaging in transactional sex, earlier age at first pregnancy, and exposure to physical IPV. We characterized three prototypical joint trajectories: abstainers (54%), early unprotected sex (36%), and high-risk sexually active (11%). We then predicted membership based on the following baseline risk and protective factors: household expenditures, bonding to school, parental monitoring, number of close friends, and community engagement. We found that school bonding and parental monitoring were the strongest predictor of sexual risk, and that, among those in both the early unprotected sex and high-risk groups, risky behaviors like unprotected and transactional sex most frequently occurred early in adolescence. These findings suggest that interventions should target girls early in adolescence, and that interventions focused at improving school bonding and promoting parental involvement may be most effective at preventing risky sexual behavior.