Summary
This systematic review and meta-analysis provide an updated and rigorous synthesis of causal evidence on the effectiveness of land tenure reforms and environmental certification in advancing forest conservation, livelihoods, and climate change mitigation in developing countries. Land tenure reforms had sufficient high-quality evidence to support a meta-analysis. The limited number of impact evaluations of certification schemes highlights an urgent need for methodologically robust studies in this area. The meta-analysis of land tenure reforms reveals no statistically significant average effect on deforestation rates, livelihoods, or carbon stock outcomes. That said, participatory forest management schemes and reforms that clarify communal or Indigenous rights appear to perform better than top-down titling interventions implemented in isolation. Despite the small number of studies in each outcome category, patterns of heterogeneity observed in the moderator analyses point to the importance of factors such as intervention scale, implementation actors, and colonial legal heritage. These dimensions may help explain variations in effectiveness and should be systematically integrated into future research and programme design.