Abstract: The present invention relates to multiple novel approaches for the generation of an immune response in an animal, such as a human, using lentivirus-based vector technology. The invention provides for the ability to mimic the efficacy of a live attenuated (LA) vaccine, without exposing the patient to the risk of disease as possible with some LA vaccines. The invention thus provides for systems of complementary conditionally replicating vectors, vectors that produce replication deficient virus like particles, and multi-antigen constructs that target a virus or microbial pathogen. The use of these materials in the practice of the invention permits the generation of robust cellular and humoral responses to the antigens presented thereby.