Sometimes the terms ‘moral’ and ‘morality’ are used in contrast to ‘immoral’ and ‘immorality’ to distinguish normatively between right and wrong, good and bad, virtue and vice. On the other hand, they may also be used descriptively to distinguish between different aspects of social life and different realms of practical reasoning. Thus morality may be contrasted with tradition or etiquette or custom and, of course, with law. There are various views about the normative relationship between law and morality, including the ‘separation thesis’ (espoused by HLA Hart, for instance) to the effect that what the law is and what it morally ought to be are two different questions. The separation thesis assumes a descriptive distinction between law and morality, and that law is properly subject to moral assessment (or ‘that law should track morality’). These assumptions raise several questions. How is morality to be distinguished from law? Why should law track morality? If law should track morality, how, if at all, is law relevant to moral reasoning? To mark the 50th anniversary of the publication of Hart’s The Concept of Law, this paper addresses each of these questions using, as a point of departure, Hart’s (largely neglected) account of what morality is and how it differs from law. My argument will be that of the various characteristics of morality identified by Hart, the one that most robustly distinguishes it from law is the function Hart attributed to it of providing ultimate standards for assessing human conduct. Because of this feature, in cases of conflict, moral reasoning trumps legal reasoning. I will also argue that the reason why morality trumps law depends on the view taken of the nature of morality. Finally, I will argue that it does not follow from the view that morality trumps law that law is irrelevant to moral reasoning.