Many knowledgeable people believe that the only real hope for halting the AIDS pandemic rests with safe and effective HIV vaccines that are delivered through a global immunization programme. When such vaccines become a reality, the size of potential target populations for HIV vaccines may well be over 100 million. The costs associated with such a large vaccination programme probably reach the multi-billion dollar level. An international consideration of financing strategies should begin in the near future in order to avoid a repetition of the lag between vaccine availability and widespread use that accompanied the introduction of hepatitis B vaccine.