Over the past decades, health care delivery has become more complex, and the traditional roles and relationships that structure this process have altered to allow new decision makers to enter the arena. Responsibility for drug safety, previously perceived by the public as belonging to regulatory bodies and physicians, has, in their eyes, now extended to the manufacturer. Increasingly, benefits from health-care goods must now be balanced against society'S demand for safety, and to this end data must be amassed and analyzed. The developing science of pharmacoepidemiology uses new technology, including data base linkages, to expand scientific knowledge on how drugs affect patients. More specifically, it monitors the effect of adverse drug reactions (ADR) in large populations, as well as determining the benefits that specific drugs yield in fighting specific ailments. The RAD-AR (Risk/Benefit Assessment of Drugs Analysis and Response) initiative was launched in 1988 by Ciba-Geigy to address the issue of drug safety, with the aim of studying and assessing drug risks and benefits, and communicating their findings to the public. In April 1988, representatives from 30 research-based pharmaceutical companies in North America, Europe and Japan, consumer organisations and the media gathered in Switzerland to participate in the first W olfsberg Conference on the perception and management of drug safety. Since then, there has been a full agenda of meetings, workshops and seminars held all over the world. Co-operative efforts between members have resulted in the design and implementation of new projects to promote drug safety in different countries. These have included the production of data resource handbooks now available for North America, the United Kingdom, Europe and Japan; these volumes list population and sample descriptions with demographic data, coding information for diagnosis, data linkage capabilities, the availability of data bases to