The problem of indirect land use change, whereby the expansion of biofuel production displaces previous land uses into forested areas, has revealed that the carbon emissions associated with biofuel production may be greater than previously anticipated. This chapter uses a case study of a biofuel certification scheme aimed at resolving this issue. The multi-stakeholder Roundtable on Sustainable Biomaterials has promoted biofuel cultivation on ‘unused’ farmland to avoid deforestation. This study traces the development of the RSB’s technical indicator for unused land, illuminating the contested process of land classification. Initially, scientific experts were attentive to how local conditions may complicate distant categorizations of land as available for plantations. Yet ultimately, the Roundtable abandons a definition of unused land that takes into account the future possibilities of local land use patterns. The outcome is a classification of unused land that is favourable to the industry players seeking certification.