952 undergraduates participated in an attempt to extend a self-concept measure based on E. H. Erikson's theory (see 34:2 and 39:5) to a measure of personality development in late adolescence. Significant differences were found between freshman and senior scores on industry, inferiority, and identity for both sexes and for males on identity diffusion. 2 follow-up studies indicated that, within the same Ss, changes in the expected direction occurred on identity, identity diffusion, and isolation, but not on industry or inferiority. Males showed a clearer pattern of increasing maturity over the 4 yr. than did females. The differential impact of the college experience on the 2 sexes and its implications for resolution of the identity crisis are discussed. (18 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.