Urban commons is still an ambiguous concept from a theoretical standpoint and diverse in empirical terms, despite its popularity among urban social movements and academic studies. As a result, it is difficult to assess their impact on the production of a more socially just city. Through a transversal analysis, this article explores the evolution of 28 urban commons in the Barcelona of the early 21st century. There are two main contributions of this innovative approach: the reduction of the existing imbalances between the theory and the existing practices; and the characterization of their urban agenda to generate processes of social and urban transformation as well as its limitations and potentialities