Crack originated in the 1970's and was introduced in the United States in Los Angeles about 1980. By 1986, crack use had spread widely. The huge profits in the crack market led to the creation of large crack trafficking groups. The conversion of cocaine to crack is a simple process and is usually performed at the mid to lower end of the drug distribution chain. In Maryland, crack is often sold in miniature resealable plastic bags and small, clear plastic vials. Crack is smoked in almost anything that will withstand heat. Some drug experts believe that recreational use of crack is impossible; addiction can occur in just a few days. User surveys suggest that casual use has declined, but a serious problem remains among frequent, hardcore users. The 1990 Maryland State survey revealed that crack and cocaine were not among the 10 most often used drugs by 12th graders in the State. Although crack use is declining in major cities, the crack epidemic may be reaching its peak in Baltimore, where new drugs are traditionally accepted later than in other cities. Citizens feel threatened by the street violence triggered by crack cocaine and want crack dealers and users out of their neighborhoods. Tables and 24 references