This issue is part of the activities of the WATERLAT-GOBACIT Network’s Thematic Area 3 (TA3), the Urban Water Cycle and Essential Public Services (http://waterlat.org/ thematic-areas/ta3/). TA3 brings together academics, students, professionals working in the public sector, practitioners from Non-Governmental Organizations, activists and members of civil society groups, and representatives of communities and users of public services, among others. The remit of this TA is broad, as the name suggests, but it has a strong focus on the political ecology of urban water, with emphasis on the politics of essential water services. Key issues addressed within this framework have been the neoliberalization of water services, social struggles against privatization and mercantilization of these services, the politics of public policy and management in the sector, water inequality and injustice in urban areas, and the contradictions and conflicts surrounding the status of water and water services as a public good, as a common good, as a commodity, as a citizenship right, and more recently, as a human right. The publication is a contribution of the Network within the framework of the Cooperation Agreement with the Public Services International (PSI) on issues of common interest (http://waterlat.org/projects/cooperation-agreement-with-the-psi/). In this case, the special issue is the outcome of the work of a member of our team of postgraduate students, Edurne Bagué, who is a native from Catalonia and is currently completing a PhD at the Centre for Higher Research and Studies on Social Anthropology (CIESAS) in Mexico City. Her research focuses on the grassroots mobilization that has been taking place in the city of Terrasa, Catalonia, seeking to end a 75-year history of privatized water supply and “remunicipalize” the service. As discussed below in relation to Article 6, Terrasa Municipality finally decided to take back the water services into public hands on 22 March 2018, as we were finishing the publication of this issue. The case of Terrasa is part of a nationwide process in Spain, whereby widespread mobilizations to oppose further privatizations of water services and to bring back under public control those systems that had been privatized have been taking place over the last decade. In TA3 we thought that producing a special issue of the Working Papers dedicated to this process could be an important contribution to the international debate, fostering further exchange of knowledge and experience on this urgent matter. I dared to propose Edurne Bagué to take responsibility for the organization of this issue, and I am glad that she accepted the challenge and brought it to fruition. I am sure that it will be received as a welcome contribution to the ongoing debates. The issue has 6 articles, authored by academics, postgraduate students, practitioners, municipal officers, among other, all of them involved in diverse ways with the social organizations participating in the campaigns.