Intracranial glioma was diagnosed during the patient's life and histologically verified in 3857 patients between 1953 and 1984 in Finland. Their survival up to the end of 1987 was analyzed, the follow-up being complete. The treatment was by operation in 1193 cases, radiation in 459 cases, both operation and radiation in 1486 cases, and neither operation nor radiation in 719 cases. The 1-year, 5-year, 10-year, and 15-year cumulative relative survival rates were 0.53, 0.29, 0.20, and 0.18, respectively. The newborn to 14-year-olds lost 56% of their life expectancy; the 15-year-olds to 44-year-olds, 71%; the 45-year-olds to 64-year-olds, 88%; and the 65-year-olds to 99-year-olds, 91%. According to the model with the best fit in regression analysis the prognosis was significantly better among young, recently diagnosed patients who had undergone both operation and radiation.