An estimated 30% to 66 % of stroke victims have poor upper extremity function at 6 months after stroke, which contributes to long-term disability in these patients. Training the affected UE of stroke patients has thus been a mainstay of neurorehabilitation. The goal of the intervention is to restore motor and daily functions. New therapeutic strategies have been developed based on principles of neurorehabilitation and motor learning. The need for comparative effectiveness research of the innovative treatments has been called for to promote evidence-based practice and translational science in stroke motor rehabilitation. Wolf and Whitall called for rigorous comparisons between unilateral and bilateral training. McCombe Waller and Whitall also indicated the importance of combining unilateral with bilateral training. For low-functioning patients, robot-assisted training is a possible approach. Identifying possible determinants for unilateral and bilateral training outcomes may also elucidate the factors that influence treatment outcomes. Outcome measures are required that have good clinimetric properties for measuring the effects of the rehabilitation strategies.