In a birth cohort of 6281 men from Aberdeen, Scotland, social class of origin, childhood intelligence, childhood behavior disturbance and education were examined as predictors of status attainment in midlife (46 to 51 years). Social class of origin, intelligence and behavior disturbance were conceptualized as correlated predictors, whose effects were hypothesized to be partially mediated by educational qualifications. A structural equation model using Full Information Maximum Likelihood estimation confirmed that education had the strongest direct effect on status attainment at midlife. Furthermore, education partially mediated the effects of social class of origin and childhood intelligence, and fully mediated the effects of behavior disturbance on status attainment. Social class of origin, childhood intelligence and behavior disturbance were strongly inter-correlated. After controlling for these associations, educational and social status attainments were influenced to a considerably greater extent by childhood intelligence than by social class of origin. (Contains 2 figures and 2 tables.)