The term offset describes a reduction in emissions or increase in sequestration of greenhouse gases (GHG) produced by one entity that is used to compensate for emissions produced by another entity. Offsets are a key component of numerous climate policy initiatives currently under discussion or consideration. Including offsets in a GHG cap-and-trade policy framework can lower the overall cost of compliance because offsets can often be achieved at lower costs than comparably sized reductions in emissions from regulated facilities. Regardless of how offsets are achieved, accounting for the net GHG mitigation benefit produced by an activity is absolutely critical. Numerous approaches have been developed under voluntary, regional, and international markets to account for the mitigation achieved by various offset activities. This diversity in approach has made the early carbon market a valuable source of innovation and test bed for carbon accounting concepts and methodologies, but has created a great deal of uncertainty in practice. This is especially true for forest management offsets, where accounting methodology development and implementation remain relatively nascent. To provide the confidence necessary for the political acceptance of offsets in new mandatory policies and the continued acceptance of offsets by the buyers, a standardization of carbon accounting methodology is needed. An analysis of the lessons offered by existing forest management protocols is a key first step in this standardization process. The analysis that follows addresses this critical research gap by conducting side-by-side trials of seven existing forest management offset protocols: • U.S. Department of Energy (DOE) 1605(b) Technical Guidelines for Voluntary Reporting of Greenhouse Gases; • Georgia Forestry Commission (GFC) Carbon Sequestration Registry Protocol; • Chicago Climate Exchange (CCX) Sustainably Managed Forests/Long-Lived Wood Products Protocols; • California Climate Action Registry (CCAR) Forest Project Protocol; • Voluntary Carbon Standard (VCS) Improved Forest Management Protocol; • a forest management protocol derived from recommended concepts and provisions in Duke University’s Harnessing Farms and Forests in the Low-Carbon Economy (HFF); and • a draft recommendation for active forest management offset projects proposed by the State of Maine for inclusion under the Regional Greenhouse Gas Initiative (RGGI).