International migration flows are shaping world politics in a variety of ways. This chapter summarizes existing evidence on the mechanisms through which these flows affect political attitudes and participation in the countries from where the migrants originate. A comparison is made between the effects of international migration on political institutions in Cape Verde and Mozambique, which both have strong migratory traditions. Emigration from Cape Verde is characterized by relatively high-skilled migration to Portugal and other Organization for Economic Cooperation and Development (OECD) countries, while emigration fromMozambique is mostly driven by unskilled labor flows into South Africa. The results that we describe show that international migration substantially increases political participation in both settings. The demand for political accountability and electoral participation substantially increases after being exposed to better democratic political norms and knowledge about electoral processes. This effect grows with citizens' social proximity, which is characterized as opportunities for personal interaction. Overall, we provide evidence that both South-North as well as South-South international migration strengthen democracy in the poorest countries.