In this longitudinal study, the authors provide support for the validity of the claim that differences in the nature of the reinforcement that adolescent girls expect from eating contribute to the development of different forms of maladaptive eating. The learned expectancy that eating is pleasurable and rewarding predicted higher levels of social/celebratory overeating across the first year of middle school but did not predict higher levels of clinical binge eating. In contrast, the expectancy that eating helps one manage negative affect predicted higher levels of binge eating but not of social/celebratory overeating across the same time period (n = 394). The results also supported a reciprocal model in which binge eating predicted higher levels of the expectancy that eating will manage negative affect but not that eating is pleasurable and rewarding; conversely, social/celebratory overeating predicted higher levels of the expectancy that eating is pleasurable and rewarding but not that eating will manage negative affect.