The functional outcome of operative and nonoperative treatment of suprascapular neuropathy was compared to determine the preferred method of treatment for each etiology of nerve injury. The predictive value of preoperative electromyography also was studied. Fifty-three patients were evaluated at least 1 year (average, 28 months) from the time of operative (n = 36) or nonoperative (n = 17) treatment. A modified American Shoulder and Elbow Surgeons self-assessment score was obtained at presentation and at final followup. Electromyography data were obtained at initial presentation. Minimal electromyographic changes associated with denervation were associated with a limited response to treatment, especially in patients with nerve compression secondary to spinoglenoid notch cysts. Pretreatment electromyographic findings, therefore, were predictive of treatment response. Overall, operative and nonoperative treatment of these suprascapular nerve injuries resulted in significant functional improvement, but the results varied depending on the etiology of the injury. Spinoglenoid notch cysts responded significantly better to operative treatment, with the results for open surgery being the same as the results for arthroscopic decompression. In addition, compressive lesions attributable to suprascapular notch entrapment had the best improvement with surgical decompression. Traumatic lesions, including traction and direct closed injuries, had an equal response to operative and nonoperative treatment. Overuse injuries did not improve with operative treatment. Viral neuritis improved with nonoperative treatment and never was treated with surgery. Overall, traumatic injuries resulted in significantly worse final outcomes than any other etiologic processes. In the nonoperative group, neuropathy secondary to spinoglenoid cysts resulted in significantly worse function. The outcome of treatment is dependent on the severity and etiology of the nerve injury, and the method of treatment.