Abstract: Why is political self-determination valuable? There must be an answer: otherwise, the many appeals to its value in democratic and anticolonial theory rest on a fundamental philosophical mistake. The dominant liberal approach explains self-determination’s value in terms of individual autonomy. However, I object that this liberal picture is at best incomplete. I argue that political equality is also necessary to satisfy the ideal of “internal” self-determination, understood as a people’s collective control—the ‘determination’ of ‘self-determination’—over its own political institutions. Consequently, only democratic peoples can be fully internally self-determining, contradicting the liberal consensus that non-democratic peoples may be fully self-determining. I propose a new liberal egalitarian account of self-determination’s value. In my view, achieving the social bases of self-respect requires self-determination. These social bases, however, constitute a social primary good. So, if self-determination is needed to secure these social bases, then self-determination is valuable because it is needed for social justice. Self-determination’s value is thus explained via the liberal egalitarian social bases of self-respect. In short, if justice matters, then so does self-determination.