In general, the role of electromyography in the electrodiagnostic evaluation of peripheral nervous system disorders is both indispensible and complementary to nerve conduction studies. In the evaluation of typical cases of carpal tunnel syndrome, however, the specific role of thenar electromyography has been more controversial. This article focuses on the relative value of thenar electromyography in determining sensitivity, severity, and prognosis of carpal tunnel syndrome, showing that its specific value in the workup of this disorder is quite diminished, providing information which usually has already been gained by nerve conduction studies.