A. Context Biofuels are today one of the only direct substitutes for oil in road transport, available on a significant scale. They can be used today, in existing vehicle engines, unmodified for low blends, or with cheap modifications to accept high blends. Biofuels are expected to represent a substantial part of the 10% target for renewable energy in transport by 2020, set by the European Commission in its Renewable Energy Directive 2009/28/EC. With biofuels reaching a visible scale at the European level, discussions have emerged about the sustainability of biofuels compared to fossil fuels. It is clear that policy should make sure that the use of biofuels in the transport sector should happen in a sustainable way that balances the main transport related challenges of greenhouse gas reduction, reducing oil dependency and improving air quality. Specifically for the Belgian situation, BIOSES is a research project assisting the Belgian government in setting a roadmap for biofuels and analysing the potential impact that biofuel introduction may have on greenhouse gas emissions, energy use and air quality. B. Objectives The project develops different scenarios for the introduction of biofuels, based on the technological evolution in vehicle models, the likely biofuel blends on the European markets, and the possible interest of certain end user groups. Based on up-to-date data (complemented with own measurements) of energy use, emissions and cost projections, the practical feasibility and the ecological and economic impact (on micro and macro level) of the introduction of biofuels in Belgium are analysed. Results are used to create a roadmap for the introduction of biofuels in Belgium. C. Conclusions The main biofuel options for Belgium on the short term are biodiesel (methyl ester) from vegetable oil, to be blended with diesel fuel (up to B7), potentially supplemented with hydro-treated vegetable oil (HVO) in the future, and bio-ethanol from sugar or starch crops, to be blended with gasoline fuel (up to E10). Next to general blending, also options of high blends or pure biofuels could be envisaged (such as E85, ED95, B30, B100, PPO, bio-methane).