PurposeOne of the greatest challenges facing forensic practitioners is motivating offenders to engage in treatment. Possibly one of the hardest groups to engage and comply with prison regimes are young people in prison (YPP) aged 15‐17 years. Whilst there has been research interest in adult offender treatment motivation, little attention has been paid to motivation in imprisoned juveniles. The purpose of this paper is to report the adaptation of the existing adult motivational enhancement tool – the Personal Aspiration and Concerns Inventory for Offenders (PACI‐O) – for use with a YPP population and to explore the motivational effect of the PACI‐O‐YPV (Young Person's Version) on YPP.Design/methodology/approachIn total, 18 YPP took part, with nine participants each in the control and experimental groups. All participants completed the Satisfaction with Life Scale (SWLS) and their prison regime status was recorded. The experimental group completed the PACI‐O‐YPV.FindingsResults showed YPP who completed the PACI‐O‐YPV displayed an improved prison regime status, indicating improved behaviour whilst in prison and increased SWLS, compared with those in the control group. These findings support previous results with adult offender samples.Research limitations/implicationsA small sample size necessitates caution in interpreting results. Further research is needed to assess the PACI‐O‐YPV's full potential.Practical implicationsLack of motivation has been identified as a salient concern among both adult and young person offender populations. Comprehensive efforts are required to enhance motivation in forensic populations.Originality/valueThis research addresses motivation enhancement in an under‐researched offender population.