An international consortium of scientists, including transport researchers from the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR), is examining the opportunities and risks of mega-cities and metropolitan areas. The primary research objective, based on the metropolis of Santiago de Chile, is to provide recommendations for strategic urban planning and to minimise problems such as traffic congestion and air pollution. Francisco Martínez, one of Chile’s leading transport researchers, summarises the results and reasons for cooperating with DLR in the following interview. Martínez is a professor at the Universidad de Chile, and his work focusses on transport systems, urban development and modelling raffic behaviour. In a video made by the Helmholtz Center for Environmental Research, one of the other partners on this project, Francisco Martínez and DLR transport researcher Andreas Justen review the situation in this South American metropolis.