This research critically examines implementation gaps and externality problems associated with the recent proliferation of zero deforestation commitments (ZDC) by large commodity producers. By developing and employing a hierarchical framework, we evaluate the policies and strategies of 50 leading ZDC adopters in high forest-risk commodity sectors (soy, oil palm, cattle and wood). The analysis shows that while most ZDC adopters formulated strong ZDCs, there is significant room for further refining implementation mechanisms. Specifically, it finds that weak commitment to full transparency, notably disclosure of sourcing locations and suppliers, and to independent verification, undermines ZDCs' transformative potential and ability to hold companies accountable for failure to comply with their ZDCs. Our analysis also reveals that most sampled companies do not explicitly account for the socially detrimental externalities that their ZDCs threaten to produce. Where this is acknowledged, it is acknowledged implicitly through standing commitments to full voluntary certification, especially in the wood and oil palm sector. As a result, issues related to free, prior and informed consent (FPIC) and protection of high conservation value (HVC) ecosystems are comparatively well addressed by adopters, but challenges faced by smallholders, food security risks, and indirect land use change issues are only minimally accounted for. Our results suggest that for ZDCs to contribute meaningfully to inclusive and sustainable development potential, complementarities between private and public regulatory initiatives need to be better leveraged.