1. Introduction to Transitions Towards Sustainable Mobility

Transport plays a major role in the world economy, both within countries and between countries. Button (2010) mentions several basic reasons why transport is needed. First, the heterogeneity of the earth’s surface means that resources available at one place have to be transported to other places. Second, as already indicated by Adam Smith, specialization strongly contributes to productivity and quality, but inevitably leads to transport flows. This holds even more because of the existence of economies of scale. In addition to these production-related reasons, there are reasons related to personal travel. Trips are needed for social interaction with friends and relatives, for activities such as recreation, culture and sports, and also for work (commuting), given the desire to separate work and residential activities. These reasons make clear that transport demand has become increasingly fragmented in space as well as in time, and that transport serves a broad range of needs of people and companies. Hence, transport is strongly linked to activities in other domains of consumption, production, and land use, implying that solutions of transport problems not only have to be sought in the transport domain itself, but also in these other domains. This need for a broad orientation makes transport such a fascinating field of research.