The repetitive and sometimes mundane nature of conventional rehabilitation therapy provides an ideal opportunity for development of interactive and challenging therapeutic games that have the potential to engage and motivate the players. Different game design techniques can be used to design rehabilitation games that work alongside robotics to provide an augmentative therapy to stroke patients in order to increase their compliance and motivation towards therapy. The strategy we followed to develop such a system was to (i) identify the key design parameters that can influence compliance, prolonged activity, active participation and patient motivation, (ii) use these parameters to design rehabilitation games for robot-mediated stroke-rehabilitation, (iii) investigate the effects of these parameters on motivation and performance of patients undergoing home-based rehabilitation therapy. Three main studies were conducted with healthy subjects and stroke subjects. The first study identified the effects of the design parameters on healthy players' motivation. Using the results from this study, we incorporated the parameters into rehabilitation games, following player-centric iterative design process, which were formatively evaluated during the second study with healthy subjects, stroke patients, and health-care professionals. The final study investigated the research outcomes from use of these games in three patient's homes during a 6 weeks clinical evaluation. In summary, the research undertaken during this PhD successfully identified the design techniques influencing patient motivation and adherence as well as highlighted further important elements that contribute to maintaining therapeutic interaction between patients and the therapy medium, mainly the technological usability and reliability of the system.