The contribution of pulsating duplex Doppler ultrasonography to the diagnosis of middle (MCA) and anterior (ACA) cerebral artery obstruction in one patient is reported. A 10year-old boy was admitted to the hospital for pulsating headaches (especially pronounced on physical training). He had no neurologic disabilities. His EEG and brain CT scan were normal, and so were his funduscopic examination, lumbar puncture, and laboratory tests. Transcranial color duplex Doppler ultrasonography showed very high velocities in both ACA and right MCA as a sign of suspected stenosis or spasm. Bilateral subtraction cerebral angiography performed after several months of recurrent headaches and unchanged Doppler ultrasonography findings produced an image of high degree stenosis of A1 segment of both ACA and right MCA, with signs of ‘steal syndrome’ through the posterior cerebral circulation. MRI performed one year later, after episodes of transient ischemic attacks, showed ischemic infarction in the right temporo-occipital region. The etiology of stenosis was supposed to include vasculopathy, i.e. early stage of moyamoya syndrome. Other vasculopathies were excluded by laboratory tests and clinical elaboration. It is concluded that transcranial Doppler ultrasonography is a very helpful method for detection and follow-up of the degree of stenosis of great cerebral arteries in children, and that it correlates well with cerebral angiography, yet it is not useful in diagnosing the etiology of stenosis.