Although self-esteem (SE) has been studied across the life span and across social groups, few studies have focused on the changes in self-esteem within a social group. To investigate the cohort and gender differences in SE in three-generational families (child, parent, grandparent generations), 6 members of 47 families (282 individuals) completed questionnaires assessing two operationalized factors of SE, i.e., power and worth. Each subject completed a modified semantic differential scale five times, to compare him/herself with each of the other five family members (adolescent siblings, parents, and grandparents). An analysis of the results showed that for all cohorts and both sexes, measures of worth were more stable across familial significant others than were measures of power. The parent generation was highest in stability of SE, while the younger generation was lowest in stability. The power dimension of SE reflected societal stereotypes, with fathers and grandfathers ranking the highest in the power dimension and female adolescents ranking the lowest in power. Since these results suggest that the middle generation father is the most influential member within intergenerational relationships, therapeutic intervention may wish to focus on his function and role, as a basis for group dynamic changes. (BL)