Nguyen N, Powers KA, Miller WC, et al. - Given that among adolescent girls and young women (AGYW) in sub-Saharan Africa, identification of partner types at greatest risk of HIV transmission may assist in designing tailored HIV prevention interventions, researchers performed a secondary analysis of data from AGYW (aged 13–23 years) enrolled in a randomized controlled trial of cash transfers for HIV prevention in South Africa and investigated their partner types from reported characteristics. They identified data of 2,140 AGYW visits; 1,034 AGYW made 2,968 partner reports and 63 AGYW acquired HIV infection. They identified 5 latent class analysis partner types: monogamous HIV-negative peer partner; one-time protected in-school peer partner; out-of-school older partner; anonymous out-of-school peer partner; and cohabiting with children in-school peer partner. AGYW with out-of-school older partners had 2.56 times the annual risk of HIV infection, whereas AGYW with anonymous out-of-school peer partners had 1.72 times the risk when compared with AGYW with only monogamous HIV-negative peer partners. No association of prespecified partner types with incident HIV was observed. These findings may assist in designing tailored HIV prevention interventions.