The potential value of existing data sources for further analyses is being investigated utilizing a purchase order mechanism. national dental survey and oral clinical exams conducted over the past 30 years have been identified and contracts have been made with sponsors and principal investigators to determine the status of data files. Reviews of publications and other mechanisms are being used to determine the appropriateness of additional work, with emphasis on possible trend analysis and interpretation for public policy. A workshop to discuss the existing data sources and make recommendations for future analyses was held in September, 1988.