Objective: To investigate the feasibility and potential efficacy of the Nintendo Wii for balance rehabilitation after stroke. Design: Phase II, single-blind, randomized controlled trial. Setting: Inpatient rehabilitation facility. Subjects: Thirty adults (mean age 63.6 (14.7) years) undergoing inpatient rehabilitation who were less than three months post-stroke and able to stand unsupported. Interventions: Participants were allocated to a Balance Group, using the Wii Fit Plus in standing, or Upper Limb Group, using the Wii Sports/Sports Resort in sitting. Both groups undertook three 45 minute sessions per week over two to four weeks in addition to standard care. Main measures: The primary focus was feasibility, addressed by recruitment, retention, adherence, acceptability and safety. Efficacy was evaluated by balance, mobility and upper limb outcomes. Results: Twenty-one percent of individuals screened were recruited and 86 (n = 30) of eligible people agreed to participate. Study retention and session adherence was 90 and > 99 , respectively, at two weeks; dropping to 70 and 87 at four weeks due to early discharge. All participants reported enjoying the sessions and most felt they were beneficial. No major adverse events occurred. Wii use by the Balance Group was associated with trends for improved balance, with significantly greater improvement in outcomes including the Step Test and Wii Balance Board-derived centre of pressure scores. The Upper Limb Group had larger, non-significant changes in arm function. Conclusions: A Wii-based approach appears feasible and promising for post-stroke balance rehabilitation. A larger randomized controlled trial is recommended to further investigate efficacy. ?