Background. Trials of constraint-induced movement therapy (CIT) to improve upper extremity function after stroke have usually not included an actively treated control group. Objective. This study compared a modified CIT intervention with a dose-matched control intervention that included restraint of the less affected hand and assessed for differences in motor and functional performance and health-related quality of life. Methods. This 2-group randomized controlled trial, using pretreatment and posttreatment measures, enrolled 32 patients within 6 to 40 months after onset of a first stroke (mean age, 55.7 years). They received either CIT (restraint of the less affected limb combined with intensive training of the affected limb for 2 hours daily 5 days per week for 3 weeks and restraint of the less affected hand for 5 hours outside of the rehabilitation training) or a conventional intervention with hand restraint for the same duration. Outcome measures were the Fugl-Meyer Assessment, Functional Independence Measure, Motor Activity Log, Nottingham Extended Activities of Daily Living Scale, and Stroke Impact Scale. Results. Compared with the control group, the CIT group exhibited significantly better performance in motor function, level of functional independence, mobility of extended activities during daily life, and health-related quality of life after treatment. Conclusions. The robust effects of this form of CIT were demonstrated in various aspects of outcome, including motor function, basic and extended functional ability, and quality of life.