Under the DUF system, voluntary urine specimens will be obtained from 200-300 arrestees in each city at 3-month intervals. These persons will also be interviewed about their drug use. A discussion of the rationale underlying DUF describes Washington, D.C.'s program for systematic identification of drug using arrestees by urinalysis and NIJ-sponsored research in New York City. An outline of procedures followed in the DUF system covers site selection, location of data collection in the central booking facility, sample selection, testing of urines, interviews, and data processing. Cost to the criminal justice system in terms of staff and funding are discussed. Using a question and answer format, the document highlights the system's goals, types of data collected, uses of DUF information, testing methods, and costs. It emphasizes that the program will dispute routine booking operations very little. 7 references.