In the last years, both the increase in percutaneous coronary revascularization and the instance of more reliable and individualized treatments have led interventional cardiologists to seek for a valuable adjunct to angiography in order to improve assessment and treatment of atherosclerotic coronary disease. Intravascular ultrasound (IVUS) allows precise tomographic measurement of lumen area, plaque size, and, to some extent, composition, with low risks and affordable costs. It is not yet clear whether routine use of IVUS provides a middle-to-long-term benefit in prevention of recurrent cardiovascular events. This review reports the main studies on IVUS imaging, underlining impact of ultrasound in the development of contemporary percutaneous revascularization techniques.