Observance of acceptable ethical behaviour is compulsory for good research, particularly when such research puts the well-being of humans at risk. Internationalization of clinical research in developing countries raises ethical concerns. Are the study subjects aware of, and sufficiently protected against, the inherent risks of drug testing? Public policy is called upon to minimize risks while increasing the opportunities for host countries to benefit from participation in clinical research. This paper discusses some minimum principles required for clinical trials to be ethical. Based on evidence from Mexico, the paper illustrates how factors such as: slow regulatory reforms, insufficient empowerment of regulatory agencies, and disconnection among agents increase the risks of unethical behaviour in clinical research. S At the time of writing, Fernando Santiago Rodríguez was a researcher at UNU-MERIT, Keizer Karelplein 19, 6211 TC Maastricht, The Netherlands. He is now with the International