Chapter 6 argues that social norms bring about social incentives. Social norms are shared understanding about actions that are obligatory, permitted, or forbidden. Unlike legal rules, social norms are not supported by formal sanctions. Why do social norms not simply collapse from the violation? This chapter examines several mechanisms on norm compliance. The incentive to comply with social norms derives not only from the enforcement of costly punishment by others but also from reputation building for oneself. People are concerned about social approval or disapproval in their interactions with others. Social norms are sustained through social emotions such as shame, guilt, or embarrassment. Social norms can direct people to undertake actions that are inconsistent with selfish actions. People may feel ashamed from acting in their self-interest, which fosters prosocial behavior.