Youth offending remains a significant societal concern. Cognitive-behavioral therapy (CBT) is considered one of the most helpful approaches for reducing recidivism among youth offenders, yet much existing research focuses on quantitative outcomes and offers limited insight into how youths themselves experience such interventions. This qualitative study explored youths’ perceptions of the Swedish CBT-based program Kriminalitetsprogrammet B12. Five male participants aged 17–19 were interviewed using semi-structured interviews, and the material was analyzed through thematic analysis. Six themes were identified: (1) initial attitude and motivation, (2) relationships with staff, (3) personal development, (4) social network, (5) perceived limitations in program structure, and (6) post-treatment reflection. Across participants, relational factors, such as trust, empathy, equality, and non- authoritarian communication, were described as central for engagement and change. CBT techniques, including goal-setting and cognitive restructuring, became meaningful only when delivered in an emotionally safe and supportive environment. The youths reported increased motivation, improved emotional regulation, and heightened awareness of high-risk social  influences. These findings suggest that CBT delivery for justice-involved youth depends not only on structured methods but also on relational and contextual factors, aligning with previous research on motivation, individual tailoring, and supportive therapeutic environments.