Highly active antiretroviral therapy for HIV produces dramatic reductions in morbidity and mortality for many individuals who maintain a very high level of adherence to their medications. Between 20 and 33 percent of HIV-seropositive patients will miss at least one of their medication doses over a 1 to 3 day period. To improve patient adherence, we must accurately assess non-adherence and intervene to enhance adherence. Patient self-report is the most practical method for assessing adherence, but may produce unreliable and invalid results unless optimally performed. A computer-assisted, self-administered adherence program could improve HIV-seropositive patients' adherence behaviors by accurately and efficiently assessing their medication adherence, delivering an adherence intervention to patients, and producing adherence reports for providers. Patients could routinely complete the program with minimal use of valuable and costly medical staff time. By providing a neutral and seemingly private interview, computer programs may increase patient disclosure of non-adherence. In Phase I, we successfully developed a computerized HIV medication assessment that identified serious patient medication errors and non-adherence. Phase II efforts will be directed toward simplifying the adherence assessment, developing the intervention component of the adherence program, and testing the complete program's efficacy in reducing regimen misunderstandings and enhancing patient adherence. PROPOSED COMMERCIAL APPLICATIONS: Because of their heavy financial investment in improving patient adherence, a strategic alliance with a pharmaceutical company will be our primary marketing strategy. Because nonadherence increases patient morbidity and health care costs, health maintenance organizations would be a second potential market. Individual health care providers may be a third market.