In advanced countries the incidence of cardiovascular diseases is constantly increasing. During the last century many resources were employed to investigate atherosclerosis in relation to the main risk factors and to modification of lifestyles. Technologies have been developed to identify atherosclerosis in the sub-clinical phase. Measurement of the carotid intima-media thickness (IMT) by B-mode ultrasound is a well-validated procedure to detect the early stages of atherosclerosis and to track progression of atherosclerosis whereas other techniques have limited utility because of their invasive nature or limited sensitivity and reproducibility. In comparison with angiography, B-mode ultrasound has greater sensitivity for detecting early atherosclerosis and plaques at risk of rupture. IMT is associated with the severity of atherosclerosis in different vascular districts and has been measured in several clinical studies in order to assess the influence of risk factors, therapies and diet. It is also validated for drug evaluation. In spite of this evidence IMT measurement is not routinely performed in patients with high and middle levels of risk for cardiovascular diseases. Scientific societies and specifically those involved in ultrasonography should promote wider recognition of the diagnostic power of ultrasonic IMT by emphasizing the low costs and low risk of use of the instruments and its major contribution to knowledge, evaluation and monitoring of the progression of atherosclerosis.