What is the relationship between harm and disease? Discussions of the relationship between harm and disease typically suffer from two shortcomings. First, they offer relatively little analysis of the concept of harm itself, focusing instead on examples of clear cases of harm such as death and dismemberment. This makes it difficult to evaluate such accounts in borderline cases, where the putative harms are less severe. Second, they assume that harm-based accounts of disease must be understood normatively rather than naturalistically, in the sense that they are inherently value based. This makes such accounts vulnerable to more general objections of normative accounts of disease. Here we draw on an influential account of harm from the philosophy of law to develop a harm-based account of disease that overcomes both of these shortcomings.