The Berlin Aging Study is a multidisciplinary investigation of old people aged 70 to over 100 years who live in former West Berlin. In the main study (1990–1993), a core sample of 516 individuals was closely examined in 14 sessions covering their mental and physical health, their psychological functioning, and their social and economic situation. Since then, the study has been continued as a longitudinal study, and surviving participants have been reexamined seven times.