Crack, Powder Cocaine, and Heroin: Drug Purchase and Use Patterns in Six U.S. Cities presents information collected from 2,056 recently arrested powder cocaine, crack cocaine, and heroin users from Chicago; Manhattan; Portland, Oregon; San Antonio; San Diego; and Washington, D.C. It highlights information concerning where and how arrestees obtained and used drugs. Researchers gathered information on the proximity of drug purchases to the buyer's home and neighborhood; the buyer's relationship to the seller; the elapsed time, duration, and frequency of purchases; the size and price of drug transactions; how income is generated for drug purchases; the presence of firearms during drug transactions; quantities of drugs typically used; the form of drug and mode of administration; frequency of drug use and cessation; reasons for cessation; and polydrug use patterns.