This paper explores the relationship between palliative medicine and the wider medical world. It draws on data from a focus group study in which doctors from a range of specialties talked about developing palliative care for patients with heart failure. In outlining views of the organisation of care, participants engaged in a process of negotiation about the roles and expertise of their own, and other, specialties. Our analysis considers the expertise of palliative medicine with reference to its technical and indeterminate components. It shows how these are used to promote and challenge boundaries between medical specialities and with nursing. The boundaries constructed on palliative medicine's technical contribution to care are regarded as particularly coherent within orthodox medicine. In contrast, its indeterminate expertise, represented by the ‘holistic’ and ‘psychosocial’ agendas, is potentially compromising in a medical world that prizes science and rationality. We show how the coherence of both kinds of expertise is contested by moves to extend palliative care beyond its traditional temporal (end-of-life) and pathological (cancer) fields of practice.