Why do we not have an HIV vaccine and how can we make one?

Last year, President Clinton made clear the urgent need for an effective HIV vaccine, and suggested that it should be possible to create one within ten years. The authors agree. Although recent progress should not be underestimated, many obstacles remain some technical, others not. Here, Dennis Burton (Scripps Research Institute) and John Moore (Aaron Diamond AIDS Research Center) outline their views on the state of development of an HIV vaccine and the areas in which more effort should be focused.