Since its inauguration in 1979, the Tagus-Segura Aqueduct has become one of the hydraulic infrastructures that have given rise to the highest number of inter-regional conflicts in Spain during recent decades. The aim of this paper is to analyse the political, social, environmental and economic conflicts presented in the donor (Tagus) and recipient (Segura) basins of this infrastructure. To this end, through the holding of interviews with the main stakeholders and an analysis of the regulations, an assessment has been made of the results (for and against) of those who defend maintaining this infrastructure, owing to its far-reaching social and economic impact, and those who advocate its immediate or progressive closure. In conclusion, the case analysed here has become one of the foremost inter-regional water conflicts in Spain which, currently, after the proposal and adoption of certain regulatory measures, continues to represent a conflict over water use that may be of interest and comparison in the international scope.