The great prevalence of traumatic brain injury (TBI) and its high economic costs make reducing TBI-related disability a national health care priority. In our research laboratory, CI therapy has been found to significantly improve upper extremity function for persons with chronic TBI. The results have suggested that persons with TBI are less likely to adhere to critical components of the CI therapy protocol than participants with stroke in other studies. Treatment outcomes have also been more variable. Our findings suggest that some cognitive skills appear related to treatment outcome. In addition, cognitive and behavioral deficits, commonly seen with participants with TBI, challenge the delivery of the standard CI therapy protocol with some persons. We discuss the implications of these neuropsychological factors for CI therapy used for chronic TBI and propose further research to more thoroughly investigate these issues. © 2006 - IOS Press and the authors. All rights reserved.