This is a proposal to undertake a detailed assessment of vaccine research/development needs and priorities for the upcoming decade. The investigators are at the Institute of Medicine (IOM) of the National Academy of Sciences. The IOM proposes to assess progress in vaccines of domestic priority and develop a quantitative model to rank in priority order up to 20 candidate diseases and conditions (to include infectious diseases as well as non-infectious targets for vaccine research and development), and to produce a report with recommendations, background reports. The IOM will establish a committee of about 15 national experts which will conduct a literature review and combine committee members expertise with other consultant's advice in order to identify factors that hindered or helped the development of earlier priority vaccine candidates. The IOM proposes to consider, for condition other than infectious diseases, a different measure of diseases/condition burden, as well as refined methods for measuring health-related quality of life. The model will be applied to general priorities for the next 10 years and for the next 20 years. Sensitivity analyses will include the commercial viability of specific vaccines. The final report will be released 24 months after the study begins.