This article chronicles the complex, meandering, contested, and path-dependent unfolding of the remunicipalisation agenda pursued by a range of political forces and social movements in Barcelona as it has developed over the past few years. The remunicipalisation of water services management debate in the city has been marked by increasingly convoluted and intricately intertwined and enmeshed institutional configurations, legal controversies, entrenched and contested political positions, and sustained social activism. The case of Barcelona's water supply system is emblematic of the difficulties, resistances, and contradictions that open up when a long-standing status quo is challenged by the rising momentum of an oppositional agenda. The article narrates the unfolding of the controversy, demonstrating how the institutional configuration of water supply, which is organised at a metropolitan-regional level (comprising 22 municipalities and the city of Barcelona), multiplies contestations and controversies as local governments and their power coalitions respond differently to pressures and demands for remunicipalisation. In the first part of the article, we present a brief history of the private water supply system that has been in place in Barcelona since the 19th century with a particular emphasis on the complex architecture of its post-dictatorship institutional reconfiguration. The second part focuses explicitly on the making of a water controversy during the last decade when social and political demands for remunicipalisation intensified. The third part explores the present institutional, legal, and political deadlock, concluding with possible future avenues for the remunicipalisation debate (and its associated political possibilities) as well as other avenues to strengthen the metropolitan governance of water beyond the remunicipalisation debate.