Social Cognition, Vol 1, No 1,pp 38-49 THE MASTERY HYPOTHESIS AND THE OVERJUSTIFICATION EFFECT ANN K. BOGGIANO University of Colorado DIANE N. RUBLE New York University THANE S PITTMAN Gettysburg College This study examined the hypothesis that task mastery is a critical determinant of the effect of reward on intrinsic interest. Because the negative side effects of reward on interest were assumed to result from a shift away from desire for mas tery over a challenge toward simple attainment of a reward, reward was expected to undermine interest if offered to perform a challenging but not an unchal- lenging activity. Moreover, the beneficial effect of competence information on interest was predicted to depend on whether the target activity evoked feel ings of mastery. To test the mastery hypothesis, fourth-grade children perform ed an interesting activity that varied in levels of complexity. Half of the children were provided with competence information, while the other half were not provided with this information In addition, half of the children were of fered a reward for task engagement. The pattern of results provided overall support for predictions based on mastery Based on a ground-breaking set of studies (Deci, 1971; Lepper, Greene, & Nisbett, 1973), there is now considerable documentation for the counter intuitive finding that reward made contingent on engagement with a task decreases later interest in that activity (Condry, 1977; Deci & Ryan, 1980; Lepper, 1981, in press). Interpretations of this phenomenon are derived primarily from two distinct traditions. First, according to a self -perception analysis, a person's motivations and attitudes are inferred from his or her behavior and the context in which it is performed (Bern, 1972; Nisbett & Valins, 1971). Thus, when individuals evaluate their interest after per forming a task, they are less likely to indicate that they were intrinsically motivated in the activity if they were promised a reward for performance Requests for reprints should be sent to Ann K. Boggiano, Department of Psychology, Uni versity of Colorado, Boulder, Colo. 80309. 38 0278-01 6X/82/0300-0038/$02 00' 1982 Guilford Publications, Inc.