Low A, Thin K, Davia S, et al. - Adolescent girls and young women (AGYW, aged 15–24 years) were examined for the prevalence and incidence of HIV and for correlates of HIV infection by using data from the Lesotho Population-based HIV Impact Assessment (LePHIA; a nationally representative survey of adults and children based on a multistage cluster sampling method with random selection of enumeration areas and households). In this work, 8,824 households, including 2,358 AGYW who were tested for HIV infection were interviewed. The overall population had weighted HIV prevalence of 11·1% (273 of 2,358 AGYW); 5·7% in adolescent girls aged 15–19 years (64 of 1156), and 16·7% in women aged 20–24 years (209 of 1,212). Annualized HIV incidence of 1·8% (0·8–2·8) was reported. Reporting a history of anal sex, having lived outside Lesotho in the past year, having a partner suspected or known to be HIV positive, and having two or more lifetime sexual partners (1·84, 1·21–2·78, for 2–3 lifetime sexual partners; 2·44, 1·45–4·08, for ≥ 4 lifetime sexual partners) were the correlates of prevalent infection. Researchers observed a negative correlation of maternal education with HIV prevalence in the daughters among the 570 AGYW living with their mothers. Partner age, HIV status, lack of viral load suppression, and partner employment in the past year were the factors associated with AGYW infection among AGYW with a cohabitating partner. Findings thereby emphasize improving the therapy cascade in male partners and targeting preventive interventions to AGYW who are at increased risk.