The present and future of our society are characterized by a rising proportion of old and very old people. Hopes for a longer life are not only justified but real. They are often associated, however, with negative views about old age – expectations of declining intellectual abilities and physical health, of social isolation and inactivity, economic insecurity, and social dependency. Increased quantity of life in old age, in other words, is combined with a concern about its quality. The increase in number and proportion of old and very old people in the population – often described as a slow demographic revolution – is also coupled with worries that society may have to struggle to deal with difficult issues such as the financial burden of providing for old age, increasing demands on social and medical care, growing needs for assistance and care in cases of disability, and the potential loss of a sense of purpose as individuals reach advanced old age.

On closer examination, of course, it becomes clear that many of our images of old age and aging, and the associated stresses and opportunities, are based on rather uncertain knowledge. What is old age? How is chronological age related to functional age? What is the range of aging patterns for different individuals? Are old age and aging different for men and women or for members of various social, educational, and ethnic groups and classes? In which sense is aging unavoidable, and which intervention chances are realistic?