This thesis is concerned with the impact of professional background on role fulfilment. In the United Kingdom current policy in health and social care in mental health is underpinned by integration; the idea that responsibilities can be accomplished irrespective of profession. Approved mental health practice is one example of a psychiatric statutory role and function, until recently carried out by the profession of social work, which is now extended to other, non-medical, mental health professions. This thesis aims to explore the role and experiences of current practitioners in order to understand the impact, if any, of professional background on the fulfilment of approved mental health practice and the way in which it is experienced. Qualitative data are generated through semi-structured individual interviews with twelve approved mental health practitioners: five nurses, two occupational therapists and five social workers and the use of rich pictures to supplement the interview discussions. Interpretative Phenomenological Analysis was applied to the verbatim transcripts. Key findings were that approved mental health practice can be accomplished irrespective of professional background. Its practitioners require particular shared attributes, specifically a cognitive and affective capacity to deal with and use discord and to manage the disparate emotions that occur. Conceptualised in this thesis as "pull," this finding constitutes a different understanding of the use of emotion in the workplace and provides evidence of a new emotional dimension; the active use of dissonance. Professional identity is also found to be influenced by approved mental health practice thereby turning on its head the original hypothesis of this thesis. Last, personhood is found to be an additional aspect of the moral framework for approved mental health practice and is being practiced in a different circumstance than previously considered. The implications of this work are that it challenges the perception that approved mental health practice is synonymous with the profession of social work. It also revives the theory that its normative moral framework is inherently contradictory. The present study appears to be the first to associate personhood with approved mental health practice and shows role fulfilment as sophisticated emotion management, primarily the active use of dissonance. Both provide new insights into the enactment of approved mental health practice and are important issues for the future training and development of practitioners. The influence on role of professional identity may also help policy makers better understand the impact that new ways of working in mental health might have on traditional professional roles and boundaries in integrated services.