Health authorities, at local, regional, or national levels have over the last few years expressed an increasing interest in and need for international health data comparison in pursuance of policy making and monitoring. To promote health and prevent diseases, administrations need high-quality, policy-oriented health information; information that will allow them to monitor the impact of health programs and policies and provide a means for comparison between countries as well as comparison at European Community level. This task would be greatly facilitated by the development of an EU-wide Health Information System. Such a system should consist not only of a series of indicators covering the areas of interest, but also of a telematic system for the collection and dissemination of this data and indicators. However, the development of an EU-wide Health Information System will be a difficult task - politically and technically. A number of issues have to bevery carefully considered when planning, developing and implementing such a telematic system. The principles for the design and development of the system are the subject of this article.