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The fundamental dilemma in attempts to make urban development less dependent upon mobility by car is the inability of alternatives to match the quality of accessibility provided by private motorized transport. Failure to recognize this means that bringing about environmentally more sustainable urban mobility patterns is only possible at economic, social, and political costs that are unacceptable in most societies. In this paper we identify and discuss ways out of this dilemma, in the form of solutions that pursue the goal of increasing both sustainability and accessibility. We start by contending that what people ask is not a generic mobility, but rather opportunities to participate in spatially disjointed activities. Accordingly, accessibility should be defined as the amount and the diversity of ‘spatial opportunities’ that can be reached within a certain amount of time. Solutions to the accessibility–sustainability dilemma building upon this perspective (that is, planning concepts, policy measures) have been the object of recent research at the Universiteit van Amsterdam and are discussed and we look for, and find, evidence of the feasibility of these solutions in the actual trends in the Amsterdam urban region. Some policy implications of the findings are discussed.

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Transport is one of the most significant sources of unsustainability in urban regional areas. This challenge is stimulating urban planners and decision makers to incorporate the concept of sustainability into their policy design at various levels. Despite its successful implementation in several sectors and wide recognition in academic and professional debate, sustainability is still not that evident in day-to-day regional planning practice. Interpretable measures integrating accessibility and sustainability and linking them with policy-making practice are relatively scarce. This paper aims to take some steps toward measuring sustainable accessibility, which in turn is intended to help regional planners define the potential problems and design possible alternatives at the strategic planning level for a sustainable regional transport and land use system. The proposed methodology for such measurement consists of the concept of conflicts in the planning process, job opportunity modeling, and sustainability and spatial conflict analysis. The Amsterdam urban region in the Netherlands is taken as a case study. Sustainable accessibility is measured in an integrated geographic information system environment, followed by corresponding policy implications for strategy design. The experimental study demonstrates that the indicator of sustainable accessibility can be incorporated into the process of strategic policy design.

The question investigated in this paper is how to understand urban networks, taking both place-bound activities and (quality of) transport networks into account. The description should help formulate planning questions about the development of urban networks. This paper proposes three different views: node-, density-and accessibility-based. Urban networks can morphologically be described as major nodes or concentrations of activities and physical and/or functional connections between nodes in a geographical area. Beyond this morphological description, places within an area can also be characterised by the amount and diversity of activities to be accessed by means of a transport network. This paper will compare these different views of the urban network for the northern part of the Randstad Holland conurbation (the greater Amsterdam area) by means of different spatial representations. The comparisons between the patterns of these representations can help explore the changing urban network, giving rise to planning questions, which can help formulate a planning research agenda for urban networks.