We examined whether cognitive resources are necessary to react effectively to norm transgressions of others. In Study 1, we showed that a polite verbal expression of disapproval was the most effective form of social control because perpetrators were least likely to engage in the same norm transgression again in the future. In Study 2, we manipulated cognitive load and asked participants how they would react when witnessing different uncivil behaviors. Compared to participants in the cognitive load condition, participants in the control condition were more likely to use effective forms of social control and less likely to use ineffective forms of social control. The findings are integrated with recent theorizing about normative pressures and people's reactions to deviance.