Objective: To evaluate the effectiveness of a distributed version of constraint-induced movement therapy (CIMT). Design: Within-subjects control intervention study. Setting: Outpatient rehabilitation center. Participants: Eleven persons with chronic stroke. All had active extension of at least 20°at the wrist and at least 10°for each finger of the more-affected hand. Interventions: Intensive motor training of the more-affected arm for 3 hours a day for 20 days; restraint of the other arm for 9.3 hours daily to limit its use. This intervention provides the same amount of training as provided in the conventional CIMT therapy protocol (60h) but distributes training time over twice the number of days. Main Outcome Measures: Real-world (Motor Activity Log) and laboratory motor activity (Wolf Motor Function Test, Frenchay Arm Test, Nine Hole Peg Test), strength (grip force) and spasticity (Ashworth Scale), and quality of life (QOL; Stroke Impact Scale) were assessed. Results: Participants showed significant improvements in more-affected arm real-world motor activity, laboratory motor activity, strength and spasticity, as well as in some aspects of QOL, up to 6 months after treatment (P.05). Conclusions: Distributed CIMT is a promising intervention for improving motor function and QOL in patients with chronic stroke. © 2005 by American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation.