An historic achievement was realized in Paris in December 2015 when most of the world’s greenhouse-gas (GHG) emitting countries voluntarily submitted their post-2020 plans for action on climate change. These Intended Nationally Determined Contribution plans are aimed at keeping the global temperature rise well below 2°C, but apparently, the plans will require substantial improvement to attain that goal.1 Adjusting these plans is undoubtedly complex, but regardless of the specifics, it is difficult to imagine any mitigation or adaptation plan that does not include forests and other woody vegetation. By the process of photosynthesis, plants take in the GHG carbon dioxide (CO2) from the atmosphere, and use energy from the sun to power chemical reactions with water to form sugar, a building block of life. Woody plants can accrue huge amounts of carbon from the atmosphere and these stocks persist: globally, forests store 861 (±66) Petagrams of carbon.2 This process of carbon removal and deposition into longlived storages such as forests is defined as carbon sequestration by the United Nations Framework Convention on Climate Change.3 Natural processes such as plant respiration and organic matter decomposition, as well as both natural and human-caused disturbances, emit CO2 back into the atmosphere. As such, many factors interact to determine whether a forest will function as a sink that reduces atmospheric CO2 levels and mitigates global warming, or as a 2 source of CO2. Fast-growing and well-managed forests capture more CO2 from the atmosphere than they emit and can accumulate large stocks of carbon in the vegetation and soil.4 On the other hand, deforestation represents a loss in the capacity to absorb CO2 from the atmosphere and also results in emissions of CO2. Land-use change and forestry accounted for 10-12% of global GHG emissions from 2000-2011. However, forests, as a result of their growth, were a net sink for CO2 over the 2000-2009 period by a variety of estimation methods.5 Given the critical but variable role of forests in global carbon cycling, it is crucial to communicate to policymakers and other experts involved in climate-change planning how basic forest biology and forest management translate into climate warming mitigation (hereafter referred to simply as ‘mitigation’). This Report by the Food and Agriculture Organization addresses this pressing need at an opportune time. The development of the Report was initiated during the “International Online Conference on the Economics of Climate Change Mitigation Options in the Forest Sector,” which was convened in February 2015. The Report’s goal is to provide urgently required information that is relevant for making decisions regarding policy that aims to foster low-carbon-emission forests. Moreover, it provides guidelines for enhancing socioeconomic benefits of forests in ways that can be tailored to specific needs at the regional level. An Advisory Committee formulated the Report’s outline, organized to contain an Executive Summary, Introduction, six chapters (summarized below) and a Conclusion. Each Chapter concludes with ‘Key messages’ listed as bulleted points. Most Chapters also contain sub-sections entitled ‘Bottlenecks in harnessing potentials‘ and ‘Embracing opportunities.’ There are contributions from 113 experts and 22 expert reviewers provided comments on the draft. Acronyms abound, but there is a comprehensive list of definitions at the beginning of the Report.