Clinical neurophysiology can provide valuable information in the study of movement disorders through its different techniques.Among them, surface electromyography (s-EMG) is a non-invasive technique useful for the objective evaluation of movement disorders. It provides essential information of the muscles responsible for the movement, as EMG is a direct measurement of muscle activity. It answers the question of which muscles are active, and the characteristics of their activity, such as duration, rhythmicity, pattern of activation and propagation. The EMG patterns in voluntary movements are characteristic. In the same way in the disorders of the voluntary movement, there are also characteristic abnormalities.With an adequate muscle selection and specially when used with simultaneous video recording, s-EMG becomes an essential tool in the evaluation of many movement disorders such as tremor, dystonia and myoclonus. It is an extremely helpful test in the initial neurophysiological evaluation of movement disorders, and in combination with other techniques it gives an irreplaceable information for the diagnosis and management of movement disorders.