Study Design: The purpose of this protocol is to screen potential study volunteers with HIV infection to determine if they are suitable candidates for vaccine trials. Screening will be primarily for HIV vaccine trials, but may also be for screening HIV-infected adults to participate in trials of other kinds of vaccine studies that will be enrolling HIV-infected subjects. All work will be conducted at the National Institutes of Health. HIV-infected volunteers will be recruited and screened. This protocol will be used to determine if the volunteers meet eligibility requirements for participation in trials of vaccines in HIV-infected subjects.

Subjects: Approximately 1,000 adults with HIV infection.

Study Plan: Subjects are evaluated for eligibility to participate in a vaccine trial and receive counseling on HIV-related issues. Women receive counseling on avoidance of pregnancy during a clinical trial. If it is determined that the volunteer might be eligible for a vaccine trial, additional information about trial options will be provided by telephone, mail and/or visits with a study coordinator.

Study Duration: Approximately six months for each subject.

Study Evaluations: Evaluations usually include history and physical examinations and CBC, differential, platelets, PT/PTT, chemistry panel, urinalysis, pregnancy test for women of reproductive potential, hepatitis B surface antigen, hepatitis C antibody, RPR, ELISA and Western blot for HIV, anti-dsDNA, quantitative immunoglobulins, adenovirus serology and T cell subsets (CD4/CD8). However, only those evaluations needed to determine eligibility for a particular vaccine study will be completed. Blood will also be collected for storage. If needed for eligibility in a particular vaccine study, a PPD will be administered unless subject has documentation of a negative PPD within six months prior to enrollment. In addition, other standard clinical evaluations may be done if needed to determine eligibility for a particular vaccine study.