This paper offers a critical assessment of the way the influential “conception of law as a shared activity” explains the normative component of law in general and legal obligation in particular. I argue that the conception provides a bipartite account of legal obligation: we have full-blooded legal obligation, carrying genuine practical force, and legal obligation in a perspectival sense, the purpose of which is not to engage with us in practical reasoning, but simply to state what we ought to do (...) if we should take the perspective of individuals subject to the jurisdiction of the legal system. This structural feature makes the whole account disjointed, giving it a lack of unity from which stem what I take to be its three main problems, namely, its limited scope, its failure to recognize the moral features of obligation when made to arise out of law as a shared activity, and its failure to illustrate the sense in which law is widely recognized to be a practical institution. (shrink)