Current prevention and treatment programs for substance abuse are based primarily on data collected from men, even though women have different origins and patterns of substance abuse and are more vulnerable to its adverse consequences. Young, low-income women, in particular, have largely been excluded from drug abuse studies. Furthermore, racial/ethnic differences have not been investigated in this population. The proposed study will use both qualitative and quantitative methods to identify the natural history, patterns, risk factors, and ethnic/cultural differences in club drug use among young, low income women, under the guidance of theoretic models of the Social Cognitive Theory and stages of progression in substance use. A total of 600 women from three prominent racial/ethnic groups (200 non-Hispanic white, 200 Hispanics, and 200 African Americans) between 18 and 30 years of age will be recruited in the family planning clinics at the University of Texas Medical Branch. Data on history of club drug use will be collected among these young, low-income women. Correlates to club drug use will include: a) younger age (18-24), b) favorable attitude towards club drugs; and c) multiple socio-environmental and psychobehavioral factors known to encourage drug use. In addition, the different clusters of correlates of club drug use will be assessed across ethnic groups. Our quantitative research (questionnaire survey) will provide information on whether the progress of club drug use follows patterns of other illicit drug use, while our qualitative research (face-to-face interviews) will assess the unique features of club drug use. The results will provide an understanding of the reasons behind club drug use in young, low-income women, and why some stop using, others continue, and some develop dependence. These data will also allow us to understand differences in club drug users based on ethnicity, which will ultimately lead to the design of culturally sensitive prevention strategies. These study methods and findings will be used to design a randomized controlled trial of these prevention strategies in our family I planning population of 27,000 patient visits annually.