<p>Many liberals maintain that individuals have a right to autonomy while at the same time insisting that strong group rights are unjustified. The traditional justification for this position implicitly relies on assumptions about the nature of personal identity that are increasingly controversial—in particular, the assumption that individual persons, unlike groups, persist self-identically (or “endure”) through time. If instead we assume an increasingly popular alternative four-dimensionalist (“perdurantist”) account of the nature of personal identity, then the asymmetrical treatment of individual and strong groups rights to autonomy appears <i>prima facie</i> inconsistent. For, from the perspective of four-dimensionalism, exercises of individual autonomy are metaphysically on a par with exercises of group authority: each involves exercises of authority among numerically distinct person-stages, justified by a unity relation. This raises a challenge for liberals. If perdurantism turns out to be the correct account of personal identity over time, what—if anything—would justify attributing a right to autonomy to individuals, while denying it to groups? I consider several possible responses to this challenge, none of which succeed in vindicating the orthodox liberal position fully.</p>