The stability and gender differences of self-concept during adolescence and early adulthood were studied in 894 randomly selected Finnish subjects using the shortened version of the Coopersmith (1967) Self-Esteem Inventory. There were no differences between the men and women in the total score for self-concept. In early adulthood, men scored higher than women on general self-esteem, and women scored higher on the home-parents factor in each developmental period from pre-adolescence to adulthood. The stability of self-concept, as well as its different components, was rather high. General self-esteem showed the highest predictive value for the total score 6 years later.