To evaluate the prevalence and extent of carotid atherosclerosis in a general healthy population, duplex ultrasound imaging was performed in 909 men and women aged 40–79 years as part of the prospective Bruneck Ischemic Heart Disease and Stroke Prevention Study. Atherosclerotic lesions were found in 47.8% of men and 36.3% of women. Sex differences in the prevalence rates were most pronounced from age 40 to 60 years with a convergence occurring in the 7th decade. The age range of 60–69 years was found to be the crucial period for the development of advanced carotid artery disease. The frequency of internal carotid artery stenosis (>50%) in elderly men and women (60-79 years) was 10.5 and 5.5%. In nonstenotic carotid artery disease the lumen diameter turned out to be a useful indirect measure of the vascular status.