Drug abuse and dependence produces harm in multiple areas of the lives of addicted people, but empirical support for the provision of supplemental medical and psychosocial services in drug abuse treatment to address these multidimensional life problems is equivocal. Thus, the Specific Aims of this proposal are: 1. To examine the effects of organizational linkage mechanisms to health services on drug abuse treatment patients' health, social and substance use outcomes. 2. To assess whether drug abuse treatment programs that match comprehensive supplemental service delivery to patients' problems, produce better problem-specific, and health, social, and substance use outcomes. To accomplish these aims, this project will use mixed-effects regression modeling techniques in secondary, cross-level analyses of data from the National Treatment Improvement Evaluation Study (NTIES). NTIES was a national, longitudinal evaluation of drug abuse treatment that included 6593 patients in 78 programs. Linkage types (on-site delivery, case management and referral, and referral alone) will be examined as mechanisms to increase the certainty of health service delivery in the organizational context. We hypothesize that patients in programs with stronger linkages will have greater service utilization, and better physical and mental health, social adjustment, and drug use outcomes than patients in programs with weaker linkages. This project will also assess whether the extent to which the program matches services to patients' multidimensional problems improves their health-related, social, and drug use outcomes. We hypothesize that patients in programs with more comprehensive problem-service matching will have better problem-specific and overall outcomes. The research team has extensive experience with studies of supplemental service delivery in drug abuse treatment programs, with substance abuse health services research, and with the NTIES data. This work will improve our understanding of linkage mechanisms and of problem-service matching, and quantify the extent to which medical and psychosocial services are important components of effective drug abuse treatment.