A total of 41 patients who underwent microvascular decompression to relieve disabling positional vertigo in one 12-month period were studied. At follow-up examinations 2 1/2 to 3 1/2 years after the operation, 30 patients had total relief of their symptoms or were considerably improved, to the point that they could resume normal work or other activities in which they were not able to engage before the operation. Two of the 41 patients had mild improvement, and the final 9 patients had no change in their symptoms. One patient, who had had a previous vestibular nerve section without improvement, underwent microvascular decompression of the stump as well as decompression of the opposite side with no relief: 3 of these 9 patients had clear signs of bilateral vestibular nerve compression, but elected not to undergo a second procedure at that time. One patient lost hearing as a result of the operation, and 1 who had a second operation suffered a hearing loss and subsequently underwent vestibular nerve section with improvement of the symptoms. Two patients had transient deficits related to cranial nerves IV and X. The remaining patients had no complications from the operation.