Background: People who have experienced a moderate or severe traumatic brain injury (TBI) will most likely live with motor and cognitive deficits including balance and poor mobility. These deficits may lead to limitations in activity participation, life satisfaction, and may increase the risk of falls. Improving access to rehabilitation care in the chronic phase of recovery is essential to prevent ongoing health issues. However, geographical restrictions, cost of transportation, or recently the COVID-19 pandemic restrictions may limit access to rehabilitation services. Telerehabilitation could serve as an alternative method to provide rehabilitation care while increasing access. Objectives: The overall objective of this dissertation was to understand the implementation of high-intensity telerehabilitation exercise programs for people living with a moderate or severe TBI and their family partners. This was accomplished by 1) determining the feasibility of using telerehabilitation, 2) investigating the effectiveness of high-intensity home-based telerehabilitation exercise programs on physical activity, functional mobility and dynamic balance, 3) understanding the perspectives and lived experiences of completing a telerehabilitation program, and 4) exploring how interpersonal behaviours can influence practice and be perceived in a telerehabilitation setting. Methodology: Influenced by a people-centered approach and explained by the Self-Determination Theory, this dissertation followed a mixed-method alternating single-subject design methodology. Five dyads composed of five persons living with a moderate or severe TBI and their family partners completed two high-intensity telerehabilitation programs remotely supervised, daily and weekly. The feasibility and effectiveness of the telerehabilitation programs were measured from a quantitative and qualitative perspective to replicate the clinical realities and understand all perspectives. Results: In this dissertation, the feasibility of using telerehabilitation with this population was highlighted by reporting high adherence, high usability, active engagement and safety. The effectiveness on physical activity levels, functional mobility, dynamic balance and concerns with falling was also demonstrated with no differences between the daily and weekly remote supervision schedule. The dyads described being highly satisfied, engaged, and enjoyed the remotely supervised exercise programs. The individuals with the TBI perceived more supportive behaviours than thwarting behaviours from the physiotherapist. Conclusion: This dissertation advances knowledge on telerehabilitation implementation for people living with cognitive and motor deficits following a TBI. High-intensity home-based telerehabilitation programs were shown to be feasible and effective. I introduced the importance of assessing needs-supportive and needs-thwarting interpersonal behaviours in the telerehabilitation context. Integrating these novel telerehabilitation concepts within emerging telerehabilitation models of care could significantly impact long-lasting positive health outcomes for individuals living with a moderate or severe TBI.