Pathways from street experiments to transformation: a systematic review of theories of change

In the face of the challenge of a transformation of urban mobility, experimental approaches have seen a rise: Tactical urbanism, open streets, pop–up bike lanes, and superblocks have spread globally, and under the term street experiments, an expansive body of literature has emerged. This debate is based on the notion that experiments have a transformative capacity to provide an impetus for wider change. However, the understanding of this is still limited and forms only a tacit background in most articles. This systematic review therefore analyses the implicit and explicit theories of change that underpin the literature on street experiments. From a qualitative content analysis of 62 papers, it distinguishes four perspectives: the local implementation, innovation, citizens, and critical perspective. It also identifies the theoretical frameworks and components used to analyse or conceptualise the pathways from street experiments to transformation, finding a wide range from comprehensive frameworks – such as the multi–level perspective – to smaller, inductive components. However, their added value is partially limited because they are not sufficiently empirically grounded or conceptually adapted to the specificities of street experiments. The paper concludes that to construct more robust theories of change, there is a need to use available theory to conceptualise key impact mechanisms such as “learning” or “acceptance”, inductively connect abstract theoretical models with the complex reality of street experiments, and empirically assess assumptions.