Research investigated the aptitude-treatment interaction (ATI) effects of sex and ability of subjects grouped in dyads to play the simulation game Life Career. The dependent variable was career maturity and it was hypothesized that role-taking would be an intervening variable. A blocked factorial design was employed with 576 students from grade 11 sorted into 48 dyads. Post-game test results from the Career Maturity Inventory (CMI) and from two experimenter-designed questionnaires showed that there were no differences in the dependent variable of career maturity due to treatment, treatment levels, or ATI; only unreliable differences were found on the intervening variable. Since the sampling, experimental design, and treatment appeared valid, further research focusing on the dependent and independent variables suggests itself. The utility of the CMI and the experimental questionnaires should be examined. Research should investigate: 1) the interaction between the dependent and intervening variables; 2) the relation between different learning theories and the dependent variables; and 3) the construct of role-taking. (PB)