Abstract: Human-induced causes of forest change occur at multiple scales. Yet, most governance mechanisms are designed at a single level – whether international, national, regional or local – and do not provide effective solutions for the overarching challenge of forest governance. Efforts to “decentralize” governmental arrangements frequently do not recognize the importance of complex, polycentric arrangements and are based on a presumption of a single government at one level taking charge of a policy arena, often ignoring the existence of many vibrant self-governed institutions. Polycentric institutions provide a useful framework for governance, enabling aspects of preferred solutions to be used together in efforts to protect the long-term sustainability of diverse forested social-ecological systems. By considering the interaction between actors at different levels of governance, polycentricity contributes to a more nuanced understanding of the variation in diverse governance outcomes in the management of common-pool resources based on the needs and interests of citizens and the complexity of resources and governance systems at local, regional, national, and global levels. In this paper, we discuss challenges to polycentricity such as the matching of the boundaries of those who benefit, those who contribute with the boundary of the resource. We describe some approaches that have been effectively utilized to address these challenges in forests in various parts of the world. We also provide a brief overview of how the concept of polycentricity helps in the analysis of climate change and the closely related international effort to reduce greenhouse gas emissions through degradation and deforestation (REDD).