Objective: There has been increasing recognition of the effects of vicarious exposure to client trauma on healthcare professionals working with trauma survivors. The role of supervision has been suggested as key for supporting practitioners, but little evidence exists exploring how supervision is experienced by psychologists in their practice. This study, therefore, aimed to qualitatively examine psychologists’ experiences of secondary traumatic stress (STS) and of supervision specifically related to trauma practice. Methods: Thirteen individual semi-structured interviews were conducted with practising psychologists. Interviews took place via phone or Skype and were audio-recorded, transcribed verbatim and analysed using thematic analysis. Analysis: Participants’ descriptions of their STS experiences were largely based on physical responses to exposure to trauma narratives, e.g., intrusive thoughts and images, physiological arousal and avoidant behaviours. Some participants shared positive influences that STS have had on their clinical practice. Three major themes were analysed: normalisation of STS as a response to trauma narratives, development of the therapeutic relationship to connect with trauma narratives, and significance of supervisor attributes in understanding STS experiences. Conclusion: STS should be viewed as a set of normal responses to secondary exposure to traumatic material. Supervisors play a significant role in how STS is experienced, understood and processed, which has implications for supervision practices, including the delivery of trauma-informed supervision in particular. Further research should examine the role of the type and amount of secondary trauma exposure and personal trauma histories in how STS is experienced. This study suggests that the current conceptualisation of STS may unhelpfully pathologise normal distress.