We integrate and extend the literatures on perceived organizational support (POS), organizational citizenship behavior (OCB), and comparative crosscultural management by examining whether the POS-OCB relationship is contingent on national culture. In social exchanges between the organization and its employees, employees are likely to act as good citizens in reciprocity to the support provided by their organization. At the same time, it is possible that national culture couches and hence modifies the strength of these exchanges. We use meta-analysis to test the hypotheses. To test national culture as moderator, we use country-level cultural dimensions from Hofstede. Results suggest that the POS-OCB relationship can vary across cultures. While perceived organizational support has a positive influence on citizenship, the influence is stronger in some cultural settings. Higher levels of collectivism, power distance, uncertainty avoidance, and femininity strengthen the POS-OCB relationship. Hence, the POS-OCB relationship is embedded within-and therefore moderated by-the cultural aspects of the larger society.