Trauma is overrepresented in young men in custody. Additionally, young men can experience ongoing traumatisation due to the volatile nature of the prison environment. This chapter discusses how a trauma therapy (EMDR) is offered by the Complex Needs Service (CNS) in a Young Offender Institution prison to two young men. The treatment aims of the CNS and range of trauma experiences by young men accessing the service is highlighted. The chapter also explores the importance of acknowledging the systemic issues that practitioners face when delivering trauma therapy in prisons. Suggestions on how to work with these challenges are presented. The authors also reflect on their experiences of using EMDR in the prison environment and one young man’s personal experience of engaging in EMDR therapy is outlined. Implications for practice are outlined. We conclude that it is possible to offer EMDR therapy within prisons when sensitivity to the prison’s context and person’s readiness to engage is taken into consideration at each stage of the assessment and therapy process.