The Climate Trust conducted an assessment of biochar to determine its appropriateness as a terrestrial carbon sequestration offset project. Biochar is an inert residue created by pyrolysis with the potential to rapidly sequester large amounts of carbon. This report describes what types of biochar projects can most readily qualify as high-quality greenhouse gas offsets for carbon market buyers and investors. The offset quality criteria outlined by the Offset Quality Initiative (2008) are applied to the biochar project type as a whole and to a pilot project at the Thompson Timber log yard in Philomath, Oregon. This report finds that attractive projects must meet the following three criteria. First, projects must use waste biomass that, in the absence of a project, would be left to decompose. Second, projects must produce at least 25,000 metric tons of biochar over 10 years. Third, projects must be able to account for, track, and monitor where all the produced biochar is incorporated into the soil. When applying these criteria to the pilot project in Philomath, this report finds that the pilot project could be an attractive offset project if it were to scale up to use all available waste biomass and apply it to a limited number of landscapes.