The paper recently published in Nature by Gardner et al.1 marks yet another milestone in the development of adeno-associated virus (AAV) as an effective gene delivery vehicle, and is an appropriate way to highlight the fiftieth anniversary of the discovery of AAV. Using simple intramuscular injections in primates, Gardner et al. demonstrated that they can use AAV to express a synthetic hybrid antibody-receptor decoy that has neutralizing capacity for a broad range of currently circulating HIV strains. The injected primates were protected against HIV challenge for up to 10 months. They suggest that this approach may be a novel and effective way of providing immunity to HIV.