The discussion notes that drug laws set forth rules for conduct, whereas drug policies specify a program of action. Both the formulation of drug policy and its outcome are influenced by variables that include geographical location, political and economic stability, the availability of public resources, the perceived magnitude of the drug problem, and the nature of the country's legal and judicial system. Drug policies usually aim at balancing enforcement and persuasion. Two factors that have greatly influenced drug policies worldwide over the last decade include the spread of HIV/AIDS, which has pushed policy toward a public health and medical emphasis, and cocaine trafficking and associated violence, which have pulled policy back toward a law enforcement response. Health and law enforcement objectives sometimes conflict. International cooperation in drug control began early in the 20th century. The United Nations (UN) Commission on Narcotic Drugs was established in 1946 and is the UN's central policy-making organization for drug control. The operation of the international drug control system rests on the principles of national control by countries as well as international cooperation between countries and with the UN organizations in compliance with three legally binding international treaties. Regional and sub-regional cooperation, international agencies, and nongovernmental organizations also have roles. Regulation and legalization are the focus of debate in many countries, where attention is increasingly focusing on the drug consumer both as a main source of the problem and as the only medium through which a viable solution can be reached. Figures, photographs, and reference notes