Service user involvement (SUI) in healthcare and education is an established element of government policy. Emerging research demonstrates that SUI in education can positively impact on mental health students' learning. However, limited empirical attention has been paid to the impact on practice in this area. Moreover, no research has investigated whether impact on practice is sustained. Section B describes a qualitative study exploring qualified clinical psychologists' (CPs) experiences of a placement-based service user and carer involvement (SUCI) scheme during their training. The study focused on understanding their perception of the scheme's impact on their learning and practice and whether the impact on practice was sustained. Seven CPs were interviewed, predominantly 32-33 months post-scheme. Interpretative Phenomenological Analysis was used to analyse the data. Four super-ordinate themes were identified: “Contextual and relational factors underpinning learning”; “Learning: Personal and professional development”; “The enduring impact on practice”; and “Personal reflections and meaning-making”. The findings are discussed in relation to existing literature and relevant theory, including adult learning theories and social positioning theory. The findings suggest that SUCI in placement-based learning during training can support CPs' personal and professional development and a partnership approach to practice. Two participants' experiences highlight factors raising questions regarding for whom and when SUCI may be beneficial to learning. Methodological limitations, implications for SUCI in clinical psychology training and directions for future research are presented.