B-SAT is an excel tool developed for stakeholders involved in the use of all kinds of biomass for production and consumption of electricity and heat. The development of this tool was the main aim of a joint PhD project by VITO (The Flemish Institute for Technological Research) in cooperation with the University of Antwerp and the University of Leuven. The tool offers the possibility to carry out comprehensive sustainability assessments of various bioenergy systems in a practical and efficient way addressing all three dimensions (i.e. environmental, social and economic) of sustainability.