Healthy, HIV-negative volunteers will be recruited and pre-screened to confirm that they meet all of the eligibility requirements for participation. Educational materials on DNA vaccines will be reviewed with and provided to participants before enrollment into the study. There will be 3 groups of 7 volunteers. Each group will receive a constant dose of the vaccine pGag(del fs)Pol delta PR delta RT delta IN/h (5 people) or a phosphate buffered saline (PBS) control (2 people) by intramuscular inoculation. Once safety has been established, successive groups will receive a higher dose. Study groups will receive three immunizations containing either 0.5 mg (Group 1), 1.5 mg (Group 2), or 4.0 mg (Group 3) of a DNA vaccine. Dose escalation will be initiated 5 weeks after the last volunteer in the previous dose group receives their first inoculation, providing there are no significant toxicities.