Background: Rehabilitation for cognitive-communication impairments following brain injury can be complex given the heterogenous nature of impairments post injury. Project-based intervention has the potential to improve communication skills and create a meaningful real-life context where individuals collaborate to develop a concrete product, which benefits others. While evidence for this intervention is emerging, the COVID-19 pandemic prompted increased use of telehealth interventions to serve people with brain injury. This paper aims to describe a framework for the delivery of project-based intervention via telehealth within community rehabilitation settings; and present several case studies of telehealth groups completed in the United Kingdom and the United States during the COVID-19 pandemic. Methods: A working group was formed to map the components of project-based intervention onto the rehabilitation treatment specification system (RTSS). This system is a conceptual framework that helps to explain the link between treatment theory and ingredients, allowing a clinician to clearly understand how and why a treatment works. First, a literature search was completed to identify eligible studies on project-based intervention after brain injury. Second, those studies were thematically mapped onto the RTSS to identify important intervention components. Third, the presence of these components was assessed for community brain injury groups delivered via telehealth in the United Kingdom and United States. These groups were further described using a taxonomy of social activities that help to describe the degree of meaningful social engagement. Results: The literature was described with a thematic RTSS summary. Treatment aims focus on skills training and self-efficacy, advocacy and self-empowerment, emotional well-being and quality of life, and collaboration and community belonging. Treatment ingredients involve a range of cognitive and behavioural supports to deliver meaningful activities and contexts to complete a project. Mechanisms of action involve learning by doing and cognitive and affective information processing. All four telehealth groups conducted in the United Kingdom and United States involved at least three treatment aims, >7 targets, and >8 treatment ingredients. All groups reported positive experiences from activities that involve working collaboratively to help others and contribute to society. Conclusions: Project-based intervention delivered via telehealth has the potential for supporting people with acquired brain injury to improve their communication skills and engage in meaningful, collaborative activity. Application of the RTSS helps clinicians to understand the aims and therapeutic ingredients (or clinician activities) through which a person with brain injury may achieve specific treatment targets during the rehabilitation process.