APPLICANT'S ABSTRACT: This is a revised and resubmitted application to conduct an exploratory study of substance abuse, health care access and utilization. The primary objective of this proposed research is to learn how drug users utilize and experience health care services in the San Francisco Bay Area. We will employ qualitative and quantitative methods to explore substance abusers' (IDU vs. non-IDUs) access to, utilization of and experiences in health care settings. The following are our research objectives: Specific Aim 1. How and when do drug users (IDUs vs. non-IDUs) access and experience health care services? a) What are the barriers to care? b) What is the impact of route of administration? c) What is the role of social class? d) Are there gendered differences? e) What is the effect of insurance status? f) What types/intensity of physical symptoms generate care seeking activities? g) How do the number and type of social networks influence symptom interpretation and care seeking? h) How do past treatment experiences impact perspectives of health care? Specific Aim 2: What additional health and social services needs are not being met? Individuals will qualify for inclusion in the sample by meeting minimum requirements for levels of sickness and drug use and will fall into four access categories: Private insurance, Medicare, mediCal, and no insurance. There will be a total 240 study participants, half (120) will be IDUs and half (120) will be non-IDUs. We will interview 60 self- identified (primary) users of: heroin, cocaine, methamphetamines, and marijuana. The products of this proposed project include: 1) a deeper understanding of how drug users access, utilize and experience health care services; 2) a sickness scale that has been modified for use with this study population; 3) strategies and techniques to effectively integrate qualitative and quantitative methods throughout an entire study process. 4) hypotheses that can be tested in further clinical research.