Philosophers of medicine have long sought to understand the distinction between the normal and the pathological, and have proposed a number of different accounts of “disorder.” Christopher Boorse has argued that disorder is fundamentally a factual concept, belonging to the biological sciences. Normativists disagree, and see disorder as a value-laden concept, connected to notions of “the good life.” All accounts of disorder developed to date run into difficulties, and there is a sense that the philosophical project that aims to describe our current concept of disorder has become bogged down. A number of authors have now given up trying to describe our current concept of disorder and have instead moved to revisionary projects of conceptual engineering. Eliminativists argue that we would do best to eliminate the concept of disorder, while more optimistic revisionists have proposals for new concept(s) of disorder that might better advance scientific or social progress.