SUMO is free software for road traffic simulation that has been available since 2001. In SUMO's modelling, both people and public transport can be represented and used in the simulation. SUMO contains various tools for route search for vehicles, visualisation of the simulation and calculation of pollutant emissions. The tool suite contains an extensive library and can be extended with the user's own models. DLR's first project as a member of the Eclipse Foundation will be the further development of this software.