There are at present strong indications for surgery in patients suffering from symptomatic extracranial carotid stenoses of > 70%. Surgery of coincidental aneurysms is a still debated problem, but there is general agreement that it is indicated in selected cases according to the patient's life-expectancy and size and site of the aneurysm. The coexistence of these two lesions raises a decision-making problem. We reviewed 389 endarterectomies and found 12 intracranial berry aneurysms in 10 (2.6%) patients. All the 10 patients were harbouring a symptomatic carotid stenosis of > 70%. Since the correction of a stenosis increases blood flow to an aneurysm, our approach was to first operate on the intracranial lesion and then the stenosis in 7 patients harbouring aneurysms > 5 mm. Two patients affected by small aneurysms < 5 mm of an A2 azygos and left internal carotid artery underwent left endarterectomy only. The last patient was submitted first to percutaneous angioplasty of a left stenosis, then to open surgery of a contralateral middle cerebral aneurysm and finally to intravascular occlusion of a small aneurysm of the left internal carotid bifurcation by menas of a coil; this policy was adopted in order to restore normal haemodynamic conditions before the intracranial procedure. There was no mortality or permanent morbidity following surgery for aneurysm or endarterectomy. Transient morbidity occurred in 2 cases after clipping of aneurysms of the anterior communicating and middle cerebral arteries. Our results suggest that surgery of coincidental aneurysms may give good results even when there is a severe symptomatic stenosis in the neck. Moreover, the presence of a small intracranial aneurysm does not seem to be an additional risk factor for endarterectomy. When the lesions are on different sides, it may be better to treat the stenosis first if it decreases the ipsilateral cerebral blood flow.