Migration and democracy are in a tense relationship. On the one hand, migrants have, in terms of human rights, the same legitimate claim to equal moral consideration as every citizen of a state they wish to enter. On the other hand, citizens of democratic communities have the de facto right to prevent migrants from entering their territory and to exclude them from political membership. In the following article, this tension is described against the background of four different normative models of democracy—liberal, communitarian, deliberative and agonistic—which are introduced and also discussed from a transnational or cosmopolitan perspective in the first section (I). Taking into account these different approaches in democratic theory, the second section (II) discusses three systematic questions central to the research field, namely (a) the question of the legitimacy of territorial exclusions, (b) the question of the possibilities of political membership and (c) the question of the connection between democracy and refugee protection. Finally, in a brief outlook (III), the paper argues for further research to reflect the relationship between migration and democracy more strongly from a cosmopolitan perspective, combining insights from theories that attempt to establish a legitimate global democratic order with radical democratic and deliberative elements. This could open up a perspective on migration in which migration both calls the democratic “we” and its boundaries permanently into question and thereby pushes forward processes of democratisation of borders and boundaries towards a more inclusive and more legitimate democratic order.