&NA;Three patients with excruciating glossopharyngeal neuralgia underwent microsurgical operations in the posterior cranial fossa. In each patient, neurovascular compression was found involving the posteroinferior cerebellar artery and involving the 9th and 10th cranial nerves. In two of the patients, the compression was caused by arachnoiditis and in the other by an arterial loop. In each patient, neuralgia was successfully eliminated by microvascular decompression and by section of the upper rootlets of the vagus nerve. In one patient, partial section of the 9th cranial nerve was also performed. Because of the frequent involvement of the vagus nerve in the pathogenesis of this condition, open surgery should be preferable to percutaneous thermorhizotomy, which is unable to act selectively on the 10th cranial nerve. (Neurosurgery25:630‐632, 1989)