The RBS is a brief interviewer administered HIV risk assessment that is used to determine the risk at which the participant puts herself for contracting HIV through their drug and sexual behaviors over the last thirty days. It is an abbreviated version of the Risk Behavior Assessment originally developed as part of a NIDA Cooperative Agreement. The RBS collects information on drug use; drug injecting; sexual activity; condom use; exchange of sex for drugs, money or both; and HIV-test history. The RBS takes 6-10 minutes to complete. HIV risk behaviors in the areas of drug use and sex in the previous 30 days are measured. Reliability and validity assessments of the RBS support its adequacy as a research tool for populations of drug users (Needle et al., 1995; Weatherby et al., 1994).