The literature on terrorism and the rehabilitation of terrorists is growing continuously, but primary studies of high quality are still scarce. In many countries, the number of clients convicted of terrorist offences is increasing. As such, prison and probation services serve as important actors in the prevention of recidivism and radicalisation. This scoping review identifies viable management and treatment methods and approaches to (a) prevent violent extremism in prison and probation services, and (b) manage violent extremist clients in prison and probation services. The findings of twenty-seven primary studies highlight the importance of so-called soft approaches by building trust and resilience among violent extremist clients, and facilitating their prosocial engagement. Strength-based models could be considered as an alternative to the predominant risk-oriented practices in prison and probation services.