Progress towards a more sustainable transport system has become imperative in the European Union (EU), as in many other parts of the world. Transport therefore figures prominently in the EU's Sixth environment Action programme (6EAP) and Sustainable Development Strategy. At its June 2001 summit in Gothenburg, the European Council singled out the transport sector as one of the four priority areas where sustainability policy development has to be put on a faster track. Achieving progress requires better integration of environmental considerations into all areas of transport policy-making. Equally important is to get a clear and quantitative picture of the sector and its development.