This paper investigates the effect of UN election technical assistance on post-election violence. Using original data on post-election violence as well as UN data on assistance, I provide the first statistical evidence that this type of UN assistance works: United Nations election technical assistance has helped reduce violence in the wake of elections in Latin America and Africa since 1990. I argue that the provision of such assistance in the run-up to elections can contribute to more peaceful post-election periods because it increases citizens’ trust in the announced result. When voters trust the election commission, they are also more likely to trust the announced result, which should in turn lead to fewer election challenges and less violence.