Recent changes in the organisation of the French health system include 1996's ordinances, and more recently (4th Law march 2002). The general tendency of all these reforms is the management of the health system at the regional level in France. In This paper we try to find how health data management systems could be concerned by this changes. In the first part we will explain why the health data management systems are implicated in theses changes. After that we specify the kind of information needed for strategic management of health at the regional level in Brittany. Then we discuss what information is available from all health data management systems at the regional level as far as decision making in health is concerned.