Given the enormous challenges they face, why do so many citizens in developing countries routinely turn out to vote? This Element explores a new explanation grounded in the social origins of electoral participation in emerging democracies, where mobilization requires local collective action. This Element argues that, beyond incentives to express ethnic identity and vote-buying, perceptions of social sanctioning from community-based formal and informal actors galvanize many to vote who might otherwise stay home. Sanctioning is reinforced by the ability to monitor individual turnout given the open layout and centralized locations of polling stations and the use of electoral ink that identifies voters. This argument is tested using original survey and qualitative data from Africa and Afghanistan, contributing important insights on the nature of campaigns and elections in the promotion of state-building and service delivery, and the critical role voters play reducing fears of global democratic backsliding.