This paper describes a study which examined interactive relationships between a personality variable (need for approval) and a situational variable (incentive for achievement) as determinants of transgression in temptation situations. Hypotheses were formulated that need for approval would correlate differentially with transgression when individuals were offered a self-gratifying, material incentive versus an altruistic, praiseworthy one. Subjects were 34 girls and 24 boys from seventh-grade classes. The Marlowe-Crowne Social Desirability Scale was administered to assess need for approval. Transgression was assessed with a shooting gallery game, programmed to produce a fixed score when all rules were followed. Each subject participated in two successive temptation situations under constrasting incentive conditions (presented in differing sequence for two subject groups): (1) the subject's achievement of a certain score earned a prize for himself; (2) the subject's score earned a prize for another child. Findings indicated that need for approval is differentially related to transgression behavior, i.e., as a function of the incentive for achievement. Individuals with higher need for approval tended to transgress more when the incentive was altruistic or praiseworthy; individuals with lower need for approval tended to transgress more when the incentive was self-gratifying or personally materialistic. (Author/BF)