Intravascular ultrasound (IVUS) is a catheter-based technique which provides high-resolution cross-sectional images of both, coronary lumen and vessel wall. Various scientific studies recently established IVUS as a valuable tool for the assessment of the natural history of coronary atherosclerosis and the effect of different pharmacological and non-pharmacological interventions on progression-regression of atherosclerosis. Novel technical approaches that use IVUS radiofrequency data may provide further interesting information on vessel wall characteristics but require further validation. In addition, numerous trials applied IVUS to assess the short- and long-term outcome of different percutaneous coronary interventions, including the implantation of drug-eluting stents. Besides the importance of IVUS in the field of scientific trials, IVUS can be clinically helpful for the evaluation of angiographically ambiguous lesions, guidance of catheter-based interventions, and management of complications. Settings in which IVUS may be particular useful are: ostial and bifurcation lesions; the presence of diffuse atherosclerotic disease; severely calcified or very tight lesions; relatively small vessels; diabetic patients; and if multiple, long or novel stents are implanted. This article gives an overview on the value of IVUS for the assessment of coronary atherosclerosis and percutaneous coronary interventions. In this context, we reviewed a selection of recently published IVUS studies which provide interesting new information in this field.