In the past two decades public debate about the risks, benefits, and safety associated with drugs has intensified. Public disputes over risks are brought to court when individuals seek compensation for health problems attributed to a pharmaceutical product. The issue reaches legislatures and regulatory agencies when consumer advocates seek to influence the standards of drug usage. Front-page news tends to focus on accidents or other risk events with drugs. Drug risk and drug safety have become an important political issue. Drug regulat- ory agencies have been instituted, and their responsibility has increased. The approval to market a drug is dependent on a set of sophisticated studies executed according to strict protocols and scientifically defined criteria. Drug surveillance activities have gained recognition, and reporting systems to identify drug safety problems have been strengthened. The understanding and management of drug safety is, nonetheless, beset by doubts, disagreements, and disputes. Conflict occurs over the significance of risk, the adequacy of evidence, the methodologies used to evaluate and measure risk, the standards that guide regulation, and the optimal means of communicating risk information to the public.