The purpose of this review is to critically assess the clinical efficacy of neuromuscular electrical stimulation in treating motor dysfunction in hemiplegia. Three distinct applications are reviewed in the areas of motor relearning, shoulder dysfunction, and neuroprostheses. Assessment of clinical efficacy and recommendations on clinical implementation are based on the weight of published scientific evidence. With respect to motor relearning, evidence supports the use of neuromuscular electrical stimulation to facilitate recovery of muscle strength and coordination in hemiplegia. However, effects on physical disability are uncertain. With respect to shoulder dysfunction, neuromuscular electrical stimulation decreases shoulder subluxation, at least in the short term. However, effects on shoulder pain and disability are also uncertain. With respect to neuroprosthesis systems, clinically deployable upper extremity systems must await the development of more sophisticated control methods and greater fundamental understanding of motor dysfunction in hemiplegia. The evidence for clinical feasibility of lower extremity neuroprostheses is stronger, and investigations on clinical efficacy should be pursued. In summary, the application of neuromuscular electrical stimulation for motor relearning and shoulder dysfunction are ready for more rigorous scientific and clinical assessment via large, multicenter, randomized clinical trials. However, additional investigations are needed to demonstrate the clinical feasibility of neuroprostheses applications.