Contains correspondence, patient files, forms, codes, reports, and data pertaining to the Duke Longitudinal Studies. The first study began in 1955 and the second in 1968. The first Duke Longitudinal Study, although groundbreaking, was of poor quality by recent standards, as it relied on a convenience sample of volunteers, the measuring tools were primitive, and the data were stored in a manner incompatible with even long outdated statistical packages. The Second Duke Longitudinal Study (SDLS) was of much better quality. The sample was representative of all but the most poor and marginalized. The measuring instruments were much better. The data were converted to be analyzable with modern statistical software. The SDLS enrolled approximately 500 adults, age 45-75 at baseline with approximately equal numbers of men and women. Data collection was extensive. Study participants spent two full days at the Center for the Study of Aging and completed extensive interviews of demographic and social variables; they were administered a variety of psychological tests, including memory tests and a personality inventory; physical health data were obtained via an assessment performed by a physician. At the time of the study, the SDLS was the most comprehensive and interdisciplinary in the field. The SDLS data were a goldmine. It generated nearly 500 articles in scientific journals and two highly-cited books: "Normal Aging II" and "Normal Aging III". ("Normal Aging I" was based on the First Duke Longitudinal Study.). Materials date from 1956 to 1989.