[영문]We examined feelings of usefulness to others as a predictor of disability and mortality risk in a sample of older adults (aged 70?79 years) from the MacArthur Study of Successful Aging. We examined participants' perceptions of their usefulness to friends and family, measured at a baseline interview, as a predictor of subsequent increases in self-reported mobility disability, the onset of difficulty in performing activities of daily living, or mortality occurrence over a 7-year follow-up period. Compared with older adults who frequently felt useful to others, those who never or rarely felt useful were more likely to experience an increase in disability or to die over the 7-year period, even when we accounted for a number of demographic, health status, behavioral, and psychosocial factors. This suggests that feelings of usefulness may shape health trajectories in older adults.