The Magdalena Pilot Project provided outreach to Albuquerque women sex workers who were also using illicit drugs, primarily cocaine and heroin. This initial uncontrolled trial evaluated the feasibility and potential impact of motivational interviewing (MI) on change in drug use and HIV risk behaviors. Twenty-seven women were enrolled and interviewed about their substance use, health risk behaviors, and plans for change, using the client-centered, directive method of MI. Four months later, 25 women (93%) were interviewed again to assess their drug use and health risk behaviors. Large reductions were reported in frequency (days) of drug use and sex work, with a corresponding increase in days of lawful employment. In identifying problems that most needed to be addressed in order to help them live healthier lives, the women prioritized (1) basic needs including decent housing, (2) mental health care, and (3) treatment for substance use disorders.