Sex differences in the correlations between Rotter's Internal-External (I-E) Control of Reinforcement Scale and the Omnibus Personality Inventory (OPI) are predicted, based on a theoretical expectation of a relationship between I-E and adjustment, and previous research. Both tests were administered to 140 male and 130 female college freshmen. Correlation and stepwise multiple regression analyses indicates significant correlations (po.05) between I-E and several OPI scales and factors. Sex differences were obtained in absence of sex bias in the OPI. These findings have implications for research using the I-E variable. (Author)