Background and aims: The past two decades have seen a surge of interest in the impact of working with trauma on psychological therapists’ well-being. However, the implications of therapists’ responses to trauma for the process of therapy are unknown. The existing literature carries the assumption that therapists’ strong subjective responses to traumatic material have a negative impact on the therapeutic process, but this has not been directly researched. Therefore, this thesis investigates the experiences of therapists working with clients who describe traumatic events, and how therapists consider their responses to the disclosure of traumatic material to have impacted upon the therapeutic process. Method: Semi-structured interviews were carried out with nine qualified chartered counselling psychologists with experience of working with trauma. Interview transcripts were analysed using Interpretative Phenomenological Analysis (IPA). Results: The analysis produced four superordinate themes. These were: (1) Demands and challenges in the use of self in response to trauma; (2) Dimensions of complexity in working with trauma: Conceptual, contextual, ethical, political; (3) Developing the therapeutic self in response to trauma; and (4) Valuing the therapeutic self in work with trauma. Conclusion: The research indicated that significant challenges were experienced in terms of the complex interpersonal dynamics, troubling somatic processes and ethical dilemmas in therapy with trauma. Furthermore, existing theoretical models were not sufficient to illuminate practice in these areas. Thus, this research indicates that specific 8 training and development in these areas is warranted, and a possible theoretical framework to help facilitate this is proposed. In addition, the current research supports the development of more explicitly socially contextualised approaches to trauma. Future research could usefully build on the current study by further investigating embodied processes and interpersonal dynamics, as well as the impact of therapists’ disclosure of their subjective responses in therapy with trauma.