This article examines the impact of organisational changes in UK elite sport on the professional relations among and between different healthcare providers. The article describes the processes by which demand for elite sport healthcare has increased in the UK. It further charts the subsequent response within medicine and physiotherapy and, in particular, the institutionalisation of sport-specific sub-disciplines through the introduction of specialist qualifications. Drawing on semi-structured interviews with 14 doctors and 14 physiotherapists, the article argues that organisational changes have led to intra-professional tensions within both professional groups but in qualitatively different forms reflecting the organisational traditions and professional identities of the respective disciplines. Organisational changes promoting multi-disciplinary healthcare teams have also fostered an environment conducive to high levels of inter-professional cooperation though significant elements of inter-professional conflict remain. This study illustrates how intra-professional relations are affected by specialisation, how legitimation discourses are used by different professions, and how intra- and inter-professional conflict and cooperation should be seen as highly interdependent processes.