To address concerns about the negative impacts of food supply chains in forest regions, a growing number of companies have adopted policies to influence their suppliers' behaviors. With a focus on forest-risk food supply chains, we provide a systematic review of the conservation and livelihood outcomes of the mechanisms that companies use to implement their forest-focused supply chain policies (FSPs) - certifications, codes of conduct, and market exclusion mechanisms. More than half of the 37 cases that rigorously measure the outcomes of FSP implementation mechanisms find additional conservation and livelihood benefits resulting from the policies. Positive livelihood outcomes are more common than conservation additionality and most often pertain to improvements in farm income through increases in crop yields on coffee and cocoa farms that have adopted certifications or codes of conduct. However, in some cases certifications lead to a reduction in net household income as farmers increasingly specialize in the certified commodity and spend more on food purchases. Among the five cases that examine conservation and livelihoods simultaneously, there is no evidence of tradeoffs or synergies – most often an improvement in one type of outcome is associated with no change in the other. Interactions with public conservation and agricultural policies influence the conservation gains achieved by all mechanisms, while the marketing attributes of cooperatives and buying companies play a large role in determining the livelihood outcomes associated with certification. Compliance with the forest requirements of FSP implementation mechanisms is high, but challenges to geospatial monitoring and land use related selection biases limit the overall benefits of these policies. Given the highly variable methods and limited evidence base, additional rigorous research across a greater variety of contexts is urgently needed to better understand if and when FSPs can be successful in achieving synergies between conservation and livelihoods.