The articles in this issue direct our attention to the role of concepts in medical ethics. The issue includes research that defines a concept,1 research that applies concepts to illuminate the moral aspects of various elements of medicine,2 3 and research investigating the appropriate set of concepts to teach medical students.4 In their in-depth exploration of the concept of disease in this issue, Powell and Scarffe argue that our understanding of a concept should be ‘tailored to the role that the (...) concept plays in the institutional settings in which it is deployed’.1 Their methodology takes seriously the institutional context in which a concept operates. This approach to thinking about concepts is potentially applicable very broadly in medical ethics. What is the institutional role that a concept plays? What is the work that we need the concept to do? The feature article by Powell and Scarffe proposes a new definition of a foundational concept in medicine, that of disease. On their view, ‘a biomedical state is a disease only if it implicates a biological dysfunction that is, or would be, properly disvalued’.1 They describe their definition as involving both a moral criterion (of being ‘properly disvalued’) and a biological criterion (of biological dysfunction). A number of commentators engage with Powell and Scarffe’s proposal. Tekin focuses on the moral criterion, through the example of grief and depression. …. (shrink)