I am going to destine this paper to critically summarise this process [decentralising] and the current situation about this. To do it, I will divide the work in four parts. First, I will briefly describe the general characteristics of the administrative Spanish system and I will try to remark which have been, in my opinion, the main determinants of the administrative and fiscal decentralisation process produced in Spain and its political and economic explanations.Es revisado por: http://sedici.unlp.edu.ar/handle/10915/9139Instituto de Investigaciones Económicas