Noninvasive ultrasonic biopsy (UB) is a method of detecting early arteriosclerotic changes by high-resolution ultrasound scanning of the carotid and femoral bifurcation. Six UB classes (scoring 0 to 10) have been identified in 2000 asymptomatic subjects and 600 vascular patients followed up for four years. The incidence of silent coronary ischemia (tested by effort test) and the occurrence of symptomatic events in four years are increased in advanced classes and with increasing UB score. The rate of progression (ROP) in four years to the next UB class has been defined in normal subjects (1.4% in class I, 3.1% in II, 10.7% in III, 17.9% in IV, and 79.2% in class V). In a group of 305 asymptomatic hyperlipidemic subjects and in a group of 269 diabetics the ROP (in four years) was significantly higher. Therefore ultrasonic biopsy is useful to identify subjects at risk of coronary ischemia and cardiovascular events and to follow up noninvasively the progression of arteriosclerosis.