This study integrates ability, goal setting, self-efficacy, and multiple personality traits into a common framework that explains and predicts individual performance. A mediational model was tested using LISREL 8. Ability learning goal orientation, and locus of control were positively related to self-efficacy, whereas performance goal orientation was negatively related to self-efficacy on an academic task. Self-efficacy and need for achievement were positively related to goal level, which was positively related to performance in combination with ability and self-efficacy, In addition to showing that personality traits can influence the motivational process at various stages, the results highlight the unique contributions of self-efficacy and goal level to the motivational process after the effects of ability and other individual differences have been identified.