Study information came from books, journal articles, and newspaper articles in several libraries and data bases and from interviews with Oakland police officials. The analysis showed that researchers are reluctant to say that drug abuse causes crime. However, violence is an integral part of the drug subculture, and drug users and addicts commit large numbers of crimes to support their habits. Thus, drug abuse contributes significantly to the violent crime in urban communities, and drug trafficking is a multimillion dollar business that is by far the major cause of violence in urban areas. Drug abuse is impossible to eradicate because of its high demand, although it can and must be controlled. The reasons people turn to drugs must be better understood before appropriate policies can be developed to deal with the problem of drug abuse and violence. Finally, efforts to reduce drug-related crime will require reducing the demand for drugs as well as curtailing illegal supplies of them. Chapter notes, appended statistics, and 65 references. (Author abstract modified)