This article analyses the management of urban services in Buenos Aires over the twenty century, discussing their implications for the quality services in the metropolitan area. It identifies three management models: the first, decentralized-private, evident in the first fifty years; the second, centralized-state owner, from the 50’ to the end of the 80’; and the third, introduced in the 90’. This analysis shows the relation between the urban services management and the urban deterioration in Buenos Aires. It also shows the urban amelioration together with a remarkable power concentrated by de new private services companies