Influences on HIV-infected Subjects' Willingness to Participate in Research and Ability to Give Info : This protocol is conducting interviews with individuals participating in NIH intramural HIV clinical research to identify (1) the reasons that individuals decide to participate in research and (2) their understanding of the research they enroll in. Individuals in similar types of studies, some that offer cash payments and some that do not, will be compared. Our goal is 200 subjects, 100 paid and 100 unpaid. In FY 99, we conducted a focus group and pretested the survey instrument. To date, we have interviewed 23 subjects. We continue to recruit subjects recently enrolled in HIV clinical research.