The Global Workshop on Drug Information Systems: Activities, Methods and Future Opportunities, held in Vienna from 3 to 5 December 2001, highlighted the need for an ethical framework for drug epidemiology. The present article suggests some first steps that could be taken towards developing such a framework by identifying some of the key issues for consideration. The scope of drug epidemiology is defined and attention is drawn to the current dearth of scholarship and lack of specific guidelines on the ethical issues raised by such research. The importance of ethics in drug epidemiology is explained and it is argued that a guiding framework would be helpful in promoting an understanding of some of the prominent ethical challenges in this field (for example, obtaining free and informed consent to participation, the use of inducements to recruit subjects, the protection of interviewees from violations of privacy and the risk of prosecution, and the safety of field research staff). The traditional principles of biomedical ethics are outlined and their limitations in enabling an understanding of ethical issues in drug epidemiology are considered. The utility of practical case-based approaches to ethical analysis is also discussed. The article concludes with broad recommendations for an ethical framework for drug epidemiology that can be refined in further discussion on those important issues.