Effectiveness of AIDSVAX B/E Vaccine in Intravenous Drug Users in Bangkok, Thailand

Inclusion Criteria Volunteers may be eligible for this study if they: * Are 20 to 60 years old. * Are HIV-negative. * Have used intravenous drugs in the previous 12 months. * Are available and commit to 3 years of follow-up. * Have a Thai National ID or its equivalent such as government official ID or state enterprise ID. * Are able to understand the study and pass a test showing they understand it, and give written informed consent. Exclusion Criteria Volunteers will not be eligible for this study if they: * Have a serious disease or condition, or history of a serious disease or condition such as lymphoma, that would interfere with the study. * Are HIV-positive. * Have ever received an experimental HIV-1 vaccine. * Have had or expect to have any treatments or medications that interfere with the immune system (e.g., long-term use of systemic steroids, chemotherapy, or radiation). * Have received a vaccine or immunoglobulin within 2 weeks of receiving the first study injection, or other vaccines within 4 weeks of the first study injection. * Have received immunoglobulins for a long time. * Have received non-licensed, research agents within 4 weeks of the first study injection. * Expect to miss study visits or plan to move within 36 months. * Are pregnant or breast-feeding or plan to become pregnant during the 36-month study period. * Are women who have sex with men and do not plan to use effective birth control.