The development of improved methods for the production of vaccines have fostered the use of purified subunits in place of live attenuated and whole inactivated organisms. Greater understanding of immune mechanisms has stimulated efforts to design vaccines that elicit specific mechanisms of resistance to particular pathogens. Together these forces have driven a search for novel adjuvants with specific properties optimally suited to vaccines for particular diseases. At the First International Conference on Immunology and Aging, a mini-symposium was devoted to the topic of new adjuvants. This review and the following two papers summarize the proceedings of the mini-symposium and illustrate the potential for the development of new adjuvants of greater efficacy and specificity, and the complexities involved in bringing new discoveries in adjuvants from the laboratory to the clinic.