Abstract Objective: To use kinetic assessment of the sit-to-stand movement as a means of sorting out those stroke patients at risk for falling. Design: A retrospective study, using a force platform to assess sit-to-stand performance and to determine its correlation with falls in stroke patients. Setting: Hospital-based rehabilitation units. Methods: Thirty-three stroke patients (18 fallers, 15 nonfallers) and 25 age-matched healthy subjects were included in this study. Subjects sat in an adjustable chair with their feet on two force plates and performed the standing up/sitting down movement at a self-paced, comfortable speed. Results: The rate of rise in force (dF/dT) was significantly lower in stroke fallers than in stroke nonfallers and healthy subjects (23.78 ± 17.38, 55.23 ± 31.24, and 85.96 ± 42.4 percent body weight per second, respectively [ p < .005]). The center of pressure sway in mediolateral direction during rising/ sitting down was much greater in stroke fallers than in stroke nonfallers or healthy subjects ( p < .05). Body weight distribution was asymmetric on the feet of stroke patients, with much more body weight on their sound side. Conclusions: The significantly lower rate of rise in force and greater postural sway while rising/sitting down may be useful in identifying stroke patients who are at risk for falling.