In a 30-year longitudinal study of adult women (N = 104), we addressed three questions about changes in dispositional well-being: (1) Do women increase in dispositional well-being from young adulthood to midlife? (2) Are changes in dispositional well-being related to role quality? And, (3), Are the correlates between changes in dispositional well-being and role quality dependent on the method one uses to calculate change scores? Three out of four measures of dispositional well-being showed little or no mean-level change from age 21 to age 52. The fourth measure of dispositional well-being, reflecting effective Functioning or maturity, showed a statistically significant but substantively small increase over the same 30-year period. The relation between change in dispositional well-being and role-quality was tested across the 30-year span of the longitudinal study. The results showed that positive role-quality was associated with increases on measures of effective functioning and well-bring and decreases on measures of anxiety and psychoneuroticism. The method of calculating change scores did affect results with growth modeling and residualized change results being essentially identical and difference scores resulting in fewer statistically significant findings. (C) 2000 Academic Press.