Abstract
Cities are the main contributors to pollution, resource consumption and social inequalities. Therefore, they should play a key role in the path towards a more sustainable scenario in line with SDGs and different Urban Agendas. However, there are still difficulties in their implementation and citizen can play a central role. This paper presents the Urban Action Structures (UAS), understood as entities with a catalytic capacity with respect to innovative urban policies. Methodologically, firstly, a prospective analysis from regional to international level has been developed, making it possible to identify innovative lines of action in the field of sustainable cities. Secondly, the study has focused on identifying and studying UAS that can make it possible to implement the lines of action previously identified. This paper has shown that there are already social structures that can be understood as UAS, since they implement actions aligned with the priorities of the Urban Agenda for the Basque Country and, therefore, of the SDGs. The research concludes that UAS can play a key role in facilitating the implementation of Urban Agendas. Hence, urban policies should favor the generation of UAS, in order to promote long-term urban development and to foster a more sustainable spatial planning.