Summary - The paper concerns the process of regionalization of the Italian health care service that followed the 1992-93 health care reform. The so-called "reform of the reform" has been characterized by the fact of having pursued two aims. The first is related to a further decentralization of administrative and financial competences from the State to the regions. The second concerns the promotion of efficiency and quality of health care, through the introduction of mechanisms of managed competition. After having illustrated the contents of the "reform of the reform", the paper presents data on the constitution of regional health care systems. The main finding consists in a two-fold process of regionalization: from above, with respect to the central government, and from below, with respect to the municipal level.