The relation between privacy and confidentiality is critically discussed. The need to be able to process data for epidemiology and management is presented. Too often the protection of privacy is considered to be a synonym of denying access to the patient's data. The function of the Canadian National Institute for Health Information is mentioned as as example of a wider trend to have a national focal point in the development of national databanks and for administering health information networks. Protection of privacy is considered to be the most important threat to the effectiveness of such networks.