The study was undertaken to analyze the outcomes of treatment in 37 patients with 44 non-ruptured aneurysms (NRA) at different sites. The paper presents a detailed classification of NRA, identifies individuals at risk for aneurysmal disease in whom an active search for aneurysms until they rupture is recommended to prevent aneurysmal subarachnoidal hemorrhages and their sequels. Total aneurysmal exclusion was achieved in 93.2% of the cases; the aneurysmal walls were consolidated with surgical gauze in 7.2%. There were no fatal cases. Postoperative progression of focal neurological symptoms was noted in 4 patients. In 3 patients, these symptoms were entirely reversible. All NRAs should be operated on irrespective of their size particularly in young and middle-aged patients since this is technically possible and there are no concomitant diseases that make surgery contraindicated. It is expedient to perform computed or magnetic resonance imaging in combination with angiography in risk-group patients in order to reveal or exclude aneurysm.