This report presents for the first time a detailed analysis of the distribution of primary brain tumors in a population in Australia. Data on 3,575 cases of benign and malignant tumors of the brain, cranial nerves and cranial meninges diagnosed among residents of the state of Victoria from 1982 to 1990 are used to calculate incidence rates and survival by histologic type, age and sex and to compare incidence of birthplace, socioeconomic status and year of diagnosis. No sharp decline in incidence rates is seen among those over age 60 and only small increases in incidence over the 9-year period have been observed. The overall incidence rates, distributions by histologic type, and patterns of excess incidence among those born in Southern and Eastern Europe and the Middle East are similar to observations in other geographic areas. No clear trend relating incidence and socioeconomic status is observed. Survival after brain tumor diagnosis is better among women then men (52 vs. 37% survive 5 years); this difference is attributable to the greater frequency among men of the more aggressive tumor types. The most striking male over female excess is for medulloblastoma, a type that occurs predominantly in the pediatric age group. This excess coupled with the fact that this tumor occurs at a much younger age in males may suggest the presence of a genetic predisposition in some patients with this disease.