The concept of proportionality has been central to the retributive revival in penal theory, and is the main idea underlying desert theory’s normative and practical commitment to limiting punishment. Theories of punishment combining desert-based and consequentialist considerations also appeal to proportionality as a limiting condition. In this paper, we argue that these claims are founded on an exaggerated idea of what proportionality, in itself, can offer, and in particular fail properly to consider the question of what sorts of institutional conditions are needed in order to foster robust limits on the state’s power to punish. The idea that appeals to proportionality as an abstract ideal can help to limit punishment is, we argue, a chimera...