Healthy volunteers are randomized to one of eight groups. All patients receive initial immunization with HIVAC-1e, followed by two boosts at months 8 and 12 of rgp120/HIV-1SF2 (BIOCINE), rgp120/HIV-1IIIB (Genentech), rgp120/HIV-1MN (Genentech), or gp160 MN (Immuno-AG). Additionally, half of the patients in each subunit vaccine group receive a repriming with HIVAC-1e at month 4. Subjects are followed for 18 months.