A classification of three specific syndromes of ulnar-nerve compression at the wrist and hand with representative cases is presented and reported cases have been classified according to the location of compression. In Type I (proximal lesion), there is sensory loss in the ulnar distribution as well as some distal loss. In Types II and III (distal lesions), there is, respectively, only pure motor or pure sensory deficit. An outline for preoperative evaluation is suggested for more accurate localization of the site of the injury. Surgical decompression of the usual reversible ulnar neuropraxia is the suggested treatment.