ABSTRACT: Background:We evaluated Girl Empower - an intervention that aimed to equip adolescent girls with the skills to make healthy, strategic life choices and to stay safe from sexual abuse using a cluster-randomized controlled trial with three arms: control, Girl Empower (GE), and GE+. Methods:GE delivered a life skills curriculum to girls aged 13-14 in Liberia, facilitated by local female mentors. In the GE + variation, a cash incentive payment was offered to caregivers for girls' participation in the program. We evaluated the impact of the program on seven pre-specified domains using standardized indices: sexual violence, schooling, sexual and reproductive health (SRH), psychosocial wellbeing, gender attitudes, life skills, and protective factors. Findings:Participation rates in the program were high in both GE and GE+, with the average participant attending 28 out of 32 sessions. At 24 months, the standardized effects of both GE and GE+, compared to control, on sexual violence, schooling, psychosocial wellbeing, and protective factors were small (?, ? 0.11 standard deviations [SD]) and not statistically significant at the 95% level of confidence. However, we found positive standardized effects on Gender Attitudes (GE: ?, 0.206 SD, p<0.05; GE+: ?, 0.228 SD, p<0.05), Life Skills (GE: ?, 0.224 SD, p<0.05; GE+: ?, 0.289 SD, p<0.01), and SRH (GE: ?, 0.244 SD, p<0.01; GE+: ?, 0.372 SD, p<0.01; F-test for GE = GE+: p = 0.075). Interpretation:Girl Empower led to sustained improvements in several important domains, including SRH, but did not reduce sexual violence among the target population.