Despite their growing application and worldwide diffusion, the transformative potential of experiments aimed at achieving “streets for people” rather than “streets for traffic” remains largely under researched. There is little to no comparative assessment of already existing experiments, and no critical reflection on their specific added value for systemic change. Building from a literature review and discussion, this paper aims to fill this gap by addressing the following questions: Which types of city street experiments have been undertaken in the pursuit of the vision of “streets for people” instead of “streets for traffic”? What are their backgrounds, main characteristics, and reported impacts? And perhaps most importantly: How can these city street experiments trigger systemic change in urban mobility? These elements are detailed per experiment type, in order of ascending functional complexity: the re-marking of streets, the re-purposing of car parking, the re-purposing of sections of streets, and the re-purposing of entire streets. Illustrative examples from practice include intersection repairs, parklets, the pavement to plazas programme, play streets, ciclovias and open streets. The reviewed literature documents positive impacts on physical activity, active transportation, safety and social interaction and capital, and more mixed impacts on business activity. While street experiments aim to create fundamentally different arrangements of urban mobility, their potential as triggers of a greater systemic change is unclear. This paper uses the defining characteristics of “transition experiments” – a concept derived from the field of transition studies – to develop and illustrate a framework to assess this transformative potential. In the conclusions, the review and assessment framework are used to sketch a research and policy agenda for this increasingly topical phenomenon.

Many cities and regions have embraced the concept of transit-oriented development (TOD). This paper explores how transfer of TOD as a policy concept impacts its implementation in the Netherlands. The study determined international policy ideas and tools that have contributed to implementation and tested them with Dutch experts using workshops, serious gaming and design charrettes. The findings suggest a number of factors complicating policy transfer, and that ‘softer’ transferable lessons (e.g., good actor relationships, information sharing) are much more difficult to transfer than ‘harder’ technical tools. Using policy lessons and tools in learning exercises helps to develop contextually appropriate policy solutions.

Contemporary urban lifestyles and business practices are increasingly dependent on mobility. At the same time, the negative impacts of mobility on natural and social environments are growing dramatically, as is the public outcry for their reversal. Urban planners are faced with a difficult dilemma: how to rejoin the essential role of mobility in enhancing cities' welfare and well-being with the lack of sustainability of present urban mobility practices? The paper argues that coping with this dilemma requires understanding and managing the deep intertwining of urban mobility, spatial developments, and broader socio-economic and cultural processes, but also coming to terms with the many, irreducible uncertainties of the challenge. It concludes that only a more intensive and critical interaction between different disciplines – at the very least fully integrating transport and spatial planningand between planning science and planning practice can achieve this.

For urban transportation planners these are challenging times. Mounting practical concerns are mirrored by more fundamental critiques. The latter comes together in the observation that conventional approaches do not adequately account for the irreducible uncertainty of future developments. The author's central aim is to explore whether and how an evolutionary approach can help overcome this limit. Two core hypotheses are formulated. The first is that the urban transportation system behaves in an evolutionary fashion. The second hypothesis is that, because of this, urban transportation planning needs to focus on enhancing the resilience and adaptability of the system. Changes in transport and land-use development patterns and policies, and in the broader context of the postwar period in the Amsterdam region, are analysed in order to illustrate the two core hypotheses. More general implications are also drawn.

Transport and mobility systems need to be transformed to meet climate change goals and reduce negative environmental and social effects. Despite EU policies having targeted such problems for more than three decades, transitions have been slow and geographically uneven. For effective change to happen, transport and mobility research needs fresh perspectives and better integration of knowledge from the Social Sciences and Humanities. Based on a Horizon Scanning approach, which allowed for a great deal of openness and variety in scholarly viewpoints, this paper presents a novel research agenda consisting of 8 themes and 100 research questions that may contribute to achieving environmentally sustainable mobility transitions within Europe. This research agenda highlights the need to not only support technological solutions for low-carbon mobility, but the importance of transformative policies that include new processes of knowledge production, civic participation and epistemic justice. We contend that the agenda points to the need for further research on the dynamics of science-society interactions.