To examine the implementation of a novel Acquired Brain Injury (ABI) Transition-Specific Service Model in Queensland, Australia to explore its potential for successful operationalization in a clinical context and what, if any, modifications were indicated. This study is part of a larger evaluation of the ABI Transitional Rehabilitation Service (ABITRS) Pilot Project using a Hybrid Type 1 research design. Data was drawn from a process evaluation nested within the larger study. Stirman et al.’s FRAME guided assessment of modifications made to the proposed Transition-Specific Service Model during implementation. The proposed Transition-Specific Service Model provided a foundational framework for establishing an ABI transitional rehabilitation service in Queensland. All designated key service delivery features of the model were implemented; context and content modifications occurred in response to the implementation experience. Priority areas for intervention were comprehensively addressed, with significant changes made to the proposed staffing profile to address an identified need for more senior clinicians. The ABITRS Pilot Project provided an opportunity to test and refine elements of an ABI Transition-Specific Service Model in a clinical context. Knowledge gained from this process has the potential to inform future design of transitional rehabilitation services for acquired brain injury.