The Identification of Causal Mechanisms in Sustainable Urban Transitions—A Systematic Approach to Case Selection

Cities around the world are betting on sustainable transitions as a formula to respond to some of the challenges they face. Within transitions, the acceleration phase has been little studied, perhaps because it relies on the mechanisms linked to the causes that lead to the desired effects. In the study of sustainable transitions, Qualitative Comparative Analysis is used to identify the causal conditions that generate the outcomes. Identifying causal mechanisms requires complementing this analysis with process tracing, the Set Theoretic Multi-Method Research (SMMR). Although previous work has complemented QCA analysis with process tracing, it did not apply a systematic approach to case selection. So, the research question addressed is: can we systematically select cases to apply process tracing in the explanation of sustainable urban transitions? The present work, by applying a systematic approach in the selection of the cases to which to apply process tracing, verifies the existence of a causal mechanism among the causal conditions that explains the denial of cities’ readiness to implement mobility innovations that can be extrapolated. No such mechanism exists for the analysis of readiness. Thus, the fundamental role played by lock-in mechanisms in the maintenance of the existing regimes in sustainable transitions is confirmed.