Governing the circular–digital transition: Comparative legal‐institutional analysis of smart waste strategies in Spain and Portugal

Abstract This article analyses how regulatory and governance frameworks influence the implementation of smart waste strategies in the context of the EU's circular and digital transitions. Focusing on Spain and Portugal—two EU Member States subject to shared supranational obligations but marked by divergent legal traditions and administrative structures—this paper explores how national laws, planning instruments and smart city strategies mediate the local uptake of EU environmental and digital mandates. Drawing on regulatory governance and multilevel governance theory, the article argues that smart city strategies function as soft regulatory tools whose effectiveness depends on their integration within legally binding frameworks and their articulation with institutional capacities at different levels. The findings reveal that while both countries have transposed relevant EU directives, implementation remains fragmented due to decentralised competences, variable municipal capacities and limited data governance. The article concludes that regulatory convergence alone is insufficient and calls for stronger integration mechanisms to ensure a coherent, inclusive and effective circular–digital transition.