Evidence-based practice (EBP) advocates that treatments offered to patients should be empirically supported and effective. Group-based treatment is offered in forensic mental health services as a way of assisting forensic patients (FPs) to address their offending behavior. However, little research exists examining how research and practice are integrated in these interventions, consistent with the principles of EBP. This study examined the utilization and evaluation of offense-specific group treatment programs with FPs, with a specific focus on interventions for substance misuse, sexual offending, firesetting, and violent offending. The results highlight that despite frequent use of offense-specific group interventions for FPs in UK forensic mental health services, evaluation is lacking regarding both published evaluations and through routine clinical practice. To ensure consistency with principles of EBP, recommendations are made surrounding the implementation of routine evaluations (e.g., follow-up studies) of offense-specific group treatment programs with FPs. [ABSTRACT FROM AUTHOR]