The concept of structural lag originally was suggested by the observation that in the late twentieth century there was a discrepancy between the growing number of older healthy people and the meaningful roles available to them. This simple empirical observation is only one instance of a more general phenomenon: a mismatch between the numbers and kinds of people of a given age and existing patterns in the social structures into which people must fit. This mismatch occurs because changes in people's lives and changes in social structures typically are not synchronic. When social structures fail to adapt to new cohorts with characteristics different from those of previous cohorts, there is a situation of structural lag (Riley et al. 1994).

Premises About Age and Society

How and why structural lags emerge and how they are dealt with can be better understood by considerating the underlying principles of age...