This paper provides a detailed description of the experimental design and chronology of the Evergreen Project, the aims of which were to profile the health and functional capacity of the elderly population of Jyväskylä, Finland, to examine changes in health and functional capacity over time, and to identify the factors related to living conditions and lifestyle that predict changes in functional capacity and health. Residents of Jyväskylä were invited to participate in a series of interviews and laboratory testing sessions. The interviews focused on (a) illnesses, the use of drugs, perceived health, symptoms, and psychosocial well-being, (b) physical and mental capacity and ADL functional capacity, (c) social togetherness and community activity, and (d) living conditions. lifestyle, and life history. The laboratory examinations assessed health status and drug use. anthropometric status, physical performance. sensory functions, perceptual-motor coordination, cognitive capacity and metacognitions. and neuropsychological functioning. A detailed breakdown of the participation and attrition rates, demographic characteristics, and normative data for each age cohort is provided.