• The incidence of primary intracranial neoplasms in Rochester, Minn, from 1935 through 1977 is reviewed with regard to whether the tumor was diagnosed because of symptoms arising before death or was found incidentally at autopsy. Among males, the overall age-adjusted incidence rate of cases diagnosed before death was 8.3 per 100,000 population per year, which included a rate of 4.0 for gliomas, 1.2 for meningiomas, and 1.5 for pituitary tumors. Among females, the comparable overall rate was 10.1; that included a rate of 4.1 for gliomas, 2.6 for meningiomas, and 1.7 for pituitary tumors. Of all autopsies on subjects aged 55 years and over, about 1% confirmed or discovered gliomas and slightly more than 1% confirmed or discovered meningiomas.