The persistence and strength of international norms are thought to depend partly on the willingness of actors to punish their violation, but norm enforcement is often inconsistent. This article investigates states’ use of economic sanctions in order to gain insight into the role of metanorms (norms about enforcing norms) in international politics and explain this inconsistency. The quantitative analyses examine patterns of economic sanctions and arms embargo practices across different security norms and reveal two central findings. First, international metanorms may accommodate important interstate relationships. Although severe human rights abuse, conflict, nuclear weapons development, and support for terrorist organisations tend to attract sanctions, they are infrequent in comparison with norm violations. Valued relationships between senders and targets seem to be an accepted limit to the pursuit of costly norm enforcement. Second, norm violations nevertheless remain rare, suggesting that factors other than the prospect of material punishment may encourage compliance. Indeed, by preserving interstate relationships, international metanorms may facilitate the engagement needed for socialisation and social pressures as alternative compliance mechanisms.