Punishment promotes contributions to public goods, but recent evidence suggests that its effectiveness varies across societies. Prior theorizing suggests that cross-societal differences in trust play a key role in determining the effectiveness of punishment, as a form of social norm enforcement, to promote cooperation. One line of reasoning is that punishment promotes cooperation in low-trust societies, primarily because people in such societies expect their fellow members to contribute only if there are strong incentives to do so. Yet another line of reasoning is that high trust makes punishment work, presumably because in high-trust societies people may count on each other to make contributions to public goods and also enforce norm violations by punishing free riders. This poses a puzzle of punishment: Is punishment more effective in promoting cooperation in high- or low-trust societies? In the present article, we examine this puzzle of punishment in a quantitative review of 83 studies involving 7,361 participants across 18 societies that examine the impact of punishment on cooperation in a public goods dilemma. The findings provide a clear answer: Punishment more strongly promotes cooperation in societies with high trust rather than low trust. © The Author(s) 2013.