This special edition of the Journal of Aging and Physical Activity (JAPA) contains original research articles from the Evergreen Longitudinal Study of Aging. Directed by Eino Heikkinen, head of the Finnish Center for Interdisciplinary Gerontology, in Jyvaskyla, Finland, this ongoing, population-wide project is designed to do the following: - Profile the health and functional capacity of Jyvaskyla's elderly population by applying an interdisciplinary research approach- Examine changes during five- to eight-year follow-ups- Identify the factors related to living conditions and lifestyle that predict changes in functional capacity and health (including survival, accidents, and institutionalization)Three features set this study apart from all others. First, the project is population-wide. While a small number of eligible persons were either too sick or unwilling to participate, the vast majority of the older adult population of a midsized Finnish town was successfully tested. Second, the Evergreen Project is multidisciplinary in focus, encouraging researchers from various fields to examine the relationship between physical activity and aging. This issue contains articles that explore how five distinct aspects of aging--physiological factors, survival rates, epidemiological limitations, psychosocial factors, and cognitive functioning--are affected by regular physical activity. The final distinguishing feature of the Evergreen Project is its longitudinal design. By monitoring the same individuals over an extended period of time, researchers can not only evaluate individual differences as the subjects age, but also test the effects of different treatments, lifestyles, and risk factors on subsequent behavior. In addition to the original research articles, this issue contains a special Digest that summarizes thirteen significant publications from the Evergreen Project that have appeared in other journals, plus a bibliography of seventy-five English-language publications based on the project.