Thirteen percent of Sweden's population (8.6 million) is aged 70 years or older, and this percentage is expected to increase over the coming decades. We have traced every diagnosed case of subarachnoid hemorrhage in patients older than 70 years in a well-defined catchment population of 953,000 individuals. The age-specific incidence for this group was 16 per 100,000 individuals per year, corresponding to 2.3 per 100,000 inhabitants per year. In most recent population-based surgical series on ruptured aneurysms, few patients in this age group are included, corresponding to only 20 to 25% of the actual number of patients, as shown in this study. Surgery is, in many cases, refused to the "elderly" because of age. However, patients who are neurologically intact after the bleed and who are without severe intercurrent diseases are potential candidates for surgical treatment. In our series, surgery yielded good results in two-thirds of 76 patients aged 70 to 74 years who returned to independent living in good mental condition. Among matched patients being refused surgery because of age, 75% suffered morbidity and mortality, with more than half of the patients having died within the 1st 3 months. When calculated for the entire population of Sweden, our data show that a 14% increase in the number of individuals achieving complete remedy from aneurysm rupture each year can be expected with more active therapy among the elderly. Most of these patients are between 70 and 74 years old. In the 9th decade of life, aneurysm surgery probably best remains an exception.