The role of reference group norms in self-regulation was examined from the perspective of transgressions. Results from four studies suggest that following the transgression of a reference group’s norms, individuals who strongly identify with their group report more intense feelings of guilt, an emotion reflecting an inference that "bad" behaviors are perceived as the cause of the transgression. Conversely, weakly identified individuals reported more intense feelings of shame, an emotion reflecting an inference that "bad" characteristics of the person are perceived as the cause of the transgression. The studies also explored the differential relevance of the reference groups when assessing transgressive behaviors, the counterfactual thoughts individuals have about possible causes for the transgressions, and the motivational outcomes of guilt and shame using behavioral data. Results of the studies offer insights into self-regulation, maintenance of group norms, and offer implications for alcohol consumption interventions, such as social marketing campaigns.