One challenge in contemporary political philosophy is to reconcile groups' claims for rights and collective self-determination with a liberal commitment to the priority of individuals' rights and well-being. A solution to this puzzle may rest on a justification of group rights based on shared individual interests. This presupposes the collective conception of group rights, which does not entail that a group has to be conceived of as a distinct entity, with an independent moral standing. Such a strategy would thus not lead to conflicts between the rights of a group and those of its individual members. This article argues that this strategy does not succeed in justifying genuine group rights. Shared interests cannot ground rights held by a group qua group, especially the kind of rights that national or cultural groups demand. The conclusion of this argument is that the interest theorist has to embrace a view of groups as distinct entities in order to ascribe them rights qua group. So the upshot of this article is that communitarian or full-blown nationalist justifications of collective rights may be more coherent than some liberal attempts although probably less plausible and more problematic from a normative point of view.