This article suggests a specific approach to the ways in which the concepts of power and social relations are related in the explicit definitions of power provided by Manuel Castells in the texts corresponding to his Marxist period: 1967-1982. It explores the main theoretical operations, the conceptual change moves, and the conceptions of power proposed by the Catalan sociologist on the basis of that specific relation. The study shows, among other things, the appropriation tactic deployed by Castells with respect to Poulantzas's concept of power, which reveals substantial differences between the two of them. Likewise, the article concludes that Castells has a unipolar view of power relations, since, in practice, he makes the concepts of power, capacity, and social relations equivalent. This research project is framed within the current trend of revaluation of social theory, as well as within the generalized trend in the social sciences to consider the issue of power as a general interpretation key and a renewed strategy for disciplinary articulation.
