The 1997 Annual Report on Adult and Juvenile Arrestees provides an overview of the Arrestee Drug Abuse Monitoring Program (ADAM), its methodology and data collection process, and detailed site-by-site tables summarizing results from each of the 23 participating cities. Results are presented in a number of different contexts, including age, gender, region, and use of specific drugs. This report presents the results of both drug urinalysis and self report information from adult male and female arrestees and juvenile male arrestees/detainees. Monitoring the size of the drug-using population in a particular year yields important information about the current structure of a drug problem. Thus, age-specific and gender-specific prevalence for different drugs are considered for 1997. Monitoring changes across years provides another dimension for under-standing drug problems, including increased understanding of future courses of drug epidemics. Thus, this section also considers prevalence over time for specific user-cohorts.