The United Kingdom (UK) government has commissioned numerous interventions across all stages of the criminal justice pathway for managing offenders likely to have a personality disorder, with the intention to reduce reoffending, improve psychological wellbeing, and develop workforce capabilities. Psychologically Informed Practice (PIP) models underpin these. To evaluate a modified PIP model within the post-imprisonment community stage of the Offender Personality Disorder (OPD) pathway, specifically workforce development, within all London (UK) probation supervised hostels (approved premises), we used both non-equivalent control group and pre-post repeated measure designs to compare changes in staff and offender outcomes before and after introduction of a PIP model across all 12 London approved premises. Findings revealed statistically significant improvements in a number of workforce outcomes (measured using the Personality Disorder-Knowledge, Attitudes and Skills Questionnaire and Maslach Burnout Inventory) which were moderated by age and gender. Data did not support associated improvements in resident offender outcomes (progressive moves, rearrests/reoffences, or breaches leading to recalls). The modified PIP is an effective intervention model for improving some workforce