For those committed to a particular account of the goals of health care, this approach can offer normative guidance for internal criticism of suspect professional practices (Kass 1985). But of course, there are numerous competing philosophies of health care, none of which command universal allegiance within the health professions. In fact, this approach also resonates well with those who argue that the health professions have no intrinsic domain of practice, beyond that which they can negotiate with patients (Good 1994). For those influenced by this libertarian view of professional autonomy, the normative lesson for professionals concerned about their obligations in specific cases can be simple: whatever interventions their patients will accept can be considered “treatments”, while “enhancements” are simply those interventions which individual health professionals refuse to provide (Engelhardt 1990). Unfortunately, medical historians and sociologists point out that the health professions have always been adept at adapting to the cultural beliefs and social values of the institutions and communities they serve. This is done by ‘medicalizing’ new problems so that they come to be seen as a legitimate part of medicine’s jurisdiction (Conrad 2007). Given the health professions’ philosophical pluralism and political autonomy, their own conventions seem to provide no principled way to exclude new interventions from their domain. To the extent that useful “upper-boundary” concepts are required at the policy level (e.g., for societies making health care allocation decisions) this impotence is an important failing for this approach to drawing the distinction.