Many of us take it for granted that states have a right to control the entry and settlement of non-citizens in their territories, and hardly pause to consider or evaluate the moral justifications for immigration controls. For a long time, very few political philosophers showed a great deal of interest in the subject. However, it is now attracting much more attention in the discipline. This article aims to show that we most certainly should not take it for granted that states enjoy a moral right to exclude would-be immigrants. It is neither obvious nor uncontroversial. And if we cannot find adequate justifications for the existence of such a right, then we need to re-evaluate the very backbone of current approaches to immigration policy. The paper begins with an overview of the existing academic debate about the extent of the right to freedom of movement. Next it introduces three arguments in support of the state’s right to exclude would-be immigrants which draw on claims about the collective right to self-determination. Finally it outlines three important challenges faced by these arguments in support of the state’s right to exclude.