The discussion of drug use patterns and related problems focuses on cocaine, marijuana, and heroin and on drug use by adolescents. Consideration is also paid to the link between drug use and crime. The analytical framework for understanding the nature of the drug problem and associated drug policies is concerned with the effects of drug laws on drug use, matching policies to problems, enforcement, treatment, and prevention. Drug policies in Europe are compared to those in the United States, and variations in drug problems and drug policies are examined. Future trends in U.S. drug policies and drug research are noted. 46 references, 1 note, 3 tables, and 6 figures