Purpose: Community-based programming to promote gender equity, often delivered through community-based girl groups (CBGGs, sometimes called “safe spaces”), is increasing. However, evidence is weak on how CBGGs are implemented and their effect on adolescent girls’ health and well-being. We conducted a comprehensive literature review to identify relevant CBGG programs. Methods: The review included programs with impact evaluations that used experimental or quasi-experimental design, data from 2 time points, control/comparison groups, and quantitative program effects and P values. Results: We analyzed evaluations of 30 programs (14 randomized controlled trials, 16 quasi-experimental). Although program designs varied, most programs targeted unmarried girls aged 13 to 18 years who were both in school and not in school, and who met weekly in groups of 15 to 25 girls. Nearly all programs used multisectoral approaches focusing on life skills and often economic and financial content, such as financial literacy and microsavings. Complementary activities with community members, boys, and health services were common. Across programs, evaluations reported statistically significant effects (P 50%) of times they measured outcomes related to gender and health attitudes and knowledge, education, psychosocial well-being, and economic and financial outcomes. Measures of outcomes related to girls’ health behaviors and health status had majority null findings. Conclusions: CBGG program evaluations found positive effects on girl-level outcomes that are independent of external factors, like gender norm attitudes, and suboptimal performance on health behavior and health status, which rely on other people and systems. This delivery model has promise for building girls’ assets. Complementary actions to engage girls’ social environments and structures are needed to change behaviors and health status.