Many community mental health centers have implemented peer treatment models that employ recovered former clients as cost-efficient adjunct providers. The effectiveness of these and other peer-administered interventions (PAIs) for treating depression symptoms has not been well-established. The current study is a meta-analysis of PAIs' effects on depression symptoms. Twenty-three eligible studies were identified. Study characteristics were coded by multiple raters, random-effects models were used to compare mean effect sizes, and mixed-effects models were used to test for moderation. PAIs produced significant pre-post reductions in depression symptoms (d = .5043 [95 % CI .3675-.6412]). In direct comparisons, PAIs performed as well as non-peer-administered interventions (.0848 [-.1455-.3151]), and significantly better than no-treatment conditions (.2011 [.0104-.3918]). PAIs that involved a professional in a secondary treatment role were significantly less effective than those that were purely peer-administered, and educational/skills-based PAIs produced better outcomes than those that were mainly supportive. Follow-up data, when available, indicated that PAIs' benefits were maintained. PAIs reduce depression symptoms and warrant further study. The clinical significance of PAIs' benefits, and whether they are better suited as stand-alone or adjunct treatments, remain to be established. Implications for the roles of mental health professionals are discussed.