This report presents a discussion of the adventages electronic clinical data gives, not only to the medical staff (helping them to get more accurate data about their patients) but also to the patient (receiving a better medical care). Then we present a study of the current spanish and european laws that rule about protection of medical data. Finally we present the characteristics a distributed information system managing and storing medical data should have, and the security measures to be taken if such a system is connected to a public network such as Internet.