Literature within youth settings suggests that building a positive alliance with young people may establish a foundation for initiating change, with young people relating daily improvements and achievements to outcomes developed through relationships with workers. This paper contributes to the limited evidence base capturing youth voice and their perspectives on professional relationships within the youth justice system. We conducted 11 semi-structured interviews with young people who were previously involved in youth diversion projects to understand their experiences of professional relationships in diversionary youth justice services. Data was analysed using reflexive thematic analysis. The analysis generated three themes and nine sub-themes. An overarching theme of transitional healing was identified. We describe a tripartite model of a transitional healing process, encompassing three iterative stages, from restoration through investment to regeneration. This characterises the relationship between young people and professionals as dynamic and changeable over time. There are likely many factors involved in recidivism and desistence; however, our findings suggest that the relationship is an important contributor to diversion. This study highlights and supports the benefit of youth participation in understanding what works in youth justice systems.