Analysts dispute what roles biomedical, psychosocial, and other factors play in determining the duration of morbidity and disability over the life course. Cross-sectional data from two national surveys of adults aged 25 years and over not only show, however, that age and socioeconomic status (SES) are significant predictors of self-reported physical health; they also demonstrate that the relation of age to health varies with SES features. Longitudinal research is needed to test the finding that enduring functional limitations in terms of time are actually compressed in higher SES groups. To improve well-being in our society, moreover, requires specifying why SES differences occur, and perhaps ultimately reducing socioeconomic inequality itself.