IntroductionComorbidity between Substance Use Disorders and trauma/post-traumatic stress disorder (PTSD) is common, particularly within residential treatment services. Comorbidity is associated with poorer treatment retention and treatment outcomes. Integrated treatment approaches are increasingly recommended but are still under examined in residential treatment services. This study will implement and evaluate a novel model of trauma-informed care (TIC) in a youth (18–35 years) residential substance use treatment service.Methods and analysisA single-armed, phase 1 implementation trial will be conducted in one residential treatment service. The model, co-developed with staff, incorporates: (i) workforce development in TIC through staff training and clinical supervision; adaptions to the service (ii) policies, procedures, and physical settings and (iii) treatment program adaptions (in delivery style and content) to be more trauma-informed; (iv) client screening and feedback for trauma and PTSD at service entry; and (v) the provision of support, referral and/or trauma-focused therapy to those with PTSD. Service outcomes will include adherence to the TIC model and client treatment completion. Client substance use and mental health measures will be collected at service entry, and 1-, 3-, 6- and 12-months follow up. Staff outcomes, including workplace satisfaction, burnout, and fatigue, as well as perceptions and confidence in delivering TIC will be collected at baseline, and at 3-, 6-, 12- and 18-months following training in the model. The sustainability of the delivery of the TIC model of care will be evaluated for 12 months using service and staff outcomes.Ethics and disseminationThe study has received ethical approval by the University of Queensland (Approval number: 2020000949). The results will be disseminated through publication in a peer-reviewed scientific journal, presentations at scientific conferences, and distributed via a report and presentations to the partner organization.Clinical trial registration: ACTRN12621000492853.