ABSTRACT University of Manchester Michael Fitzsimmons Doctor of Philosophy Understanding disengagement from Early Intervention Psychosis services: Perspectives from Service Users and Staff 5th July 2019 Background A consistent body of evidence has demonstrated that disengagement from Early Intervention Psychosis programmes of care is common. Investigating disengagement is important as it is associated with a number of adverse clinical and social outcomes. A qualitative understanding is required due to a paucity of evidence exploring disengagement from the perspective of service users and staff. Aim To investigate disengagement within an Early Intervention Psychosis service from the perspective of service users and staff. Methods Three separate but inter-related studies were conducted. A review of the literature using systematic methods was then followed by two primary qualitative studies conducted with 12 service users and 14 staff. The findings from both of these studies were synthesised to identify areas where there was commonality or lack of overlap between the two groups and to consider how future practice might be improved. Results The review of the quantitative literature identified factors that predicted disengagement. The review of the qualitative literature identified themes relating to both engagement and disengagement. Service user interviews, identified the quality of the therapeutic relationship and the presence of emotional distress as factors influencing disengagement. Staff interviews identified, service user characteristics and aspects of service delivery as obstacles to engagement. A synthesis generated four factors considered to influence decisions to disengage: 1) limitations of care coordinator role; 2) factors intrinsic to the service user; 3) service delivery factors; 4) reduced sense of agency attributed to continued engagement. Conclusion Results revealed that the service users interviewed and those described by care coordinators demonstrated a pattern of engagement, characterised by disengagement and re-engagement. Heightened emotional distress and reduced therapeutic alliance, influenced by any of the four identified factors, provides a milieu in which ambivalence to engage in treatment increases. In this context, disengagement is seen as a way to reduce further distress. It is proposed that further research is required: to confirm the findings of this thesis across a range of EIP services; to examine the emerging factors that may be associated with disengagement.