The present study investigated the relationships between ego identity, egocentrism, and formal operations in an adolescent setting. Also included in the study were various subscales of the different measurements, as well as grade in school and sex. It was hypothesized that a regression model could predict ego identity status from formal operations measured by the Piagetian Formal Operations Instrument (Burney, 1974) and egocentrism measured by the Adolescent Egocentrism Sociocentrism Scale (Enright, Shukla, and Lapsley, 1980). Ego identity status was determined by use of the Ego Identity Interview developed especially for adolescents by Archer (1980). The subjects were 15 males and 15 females each in grades eight, ten, twelve, and a college sophomore class. Subjects ranged in age from 13 to 24. The correlational results indicated significant and positive relationships between ego identity, formal operations, and grade. Egocentrism and sex were not found to be significantly related to ego identity per se, but egocentrism was found to be significantly negatively to vocational identity. Regression analysis revealed that grade was the most valuable predictor of ego identity, significantly explaining approximately 21 percent of the variance. Also the self-focus subscale of egocentrism, when added to grade, significantly explained 21 percent of the variance in vocational identity. Further investigation regarding the concept of egocentrism among adolescents and self-focus as it relates to vocational identity was recommended. / Doctor of Philosophy