BACKGROUND: Child contact management (CCM) is a recognized strategy to prevent TB; however, implementation is suboptimal. PREVENT was a cluster-randomized trial that evaluated the effectiveness and acceptability of a community-based intervention (CBI) to improve CCM in Lesotho.METHODS: Ten health facilities (HFs) were randomized to CBI or standard-of-care (SOC). CBI included nurse training/mentorship, health education by village health workers (VHW), adherence support, and multidisciplinary team meetings. Information on TB cases registered from February 2016 to June 2018 and their child contacts was abstracted. Outcomes were TB preventive treatment (TPT) initiation, TPT completion, and CBI acceptability. Generalized linear mixed models were used to test for differences between study arms and qualitative interview thematic analysis for acceptability.RESULTS: Among 547 registered children (CBI: n = 399; SOC: n = 148) of 426 adult TB patients, 46% were <2 years, 48% female, and 3% HIV-exposed/positive, with no significant differences between study arms. A total of 501 children initiated TPT-98% at CBI and 88% at SOC HFs (P < 0.0001). TPT completion was 82% in CBI vs. 59% in SOC sites (P = 0.048). Caregivers and providers reported that CBI was acceptable.CONCLUSION: The CBI was acceptable and significantly improved TPT initiation and completion in Lesotho, offering the opportunity to mitigate the threat of TB among children.