This paper seeks to elucidate the role played by the common good in John Finnis's arguments for a generic and presumptive moral obligation to obey the law.1 Finnis's appeal to the common good constitutes a direct challenge to liberal and philosophical anarchist denials of a generic and presumptive obligation to obey the law.2 It is questionable, however, whether Finnis has presented the strongest possible case for his position. In the first section I outline Finnis's account of the relationship between basic (...) goods, the common good, and the authority of law. Section II demonstrates how Finnis's emphasis upon the instrumental nature of the common good leaves his position vulnerable to Joseph Raz's objections3 that not all cases of law make a moral difference and that governmental authority is often unnecessary to resolve coordination problems. I argue that Raz's critique nonetheless fails adequately to address an alternative defense of the existence of a generic and presumptive obligation to obey the law, suggested by some passages in Finnis's work, according to which the common good is integral, rather than merely instrumental, to the good of individuals. In the final section I consider whether Finnis could strengthen his case for a generic and presumptive obligation to obey the law by adopting a more consistently robustaccount of the common good. (shrink)