Since the development of intravascular ultrasound in the late 1980s, the modality has been used both to image the vascular system and to direct interventions in target vessels. Intravascular ultrasound (IVUS) was initially used to image atherosclerosis and aid in its treatment, but it has more recently been employed within the venous system, allowing for both intravenous and transvenous image-guided interventions. IVUS is now used for both direct and transjugular intrahepatic portosystemic shunt placement, for transcaval liver biopsy and transcaval puncture of type II endoleaks, and for cardiac mass biopsy, among other interventions. The use of IVUS not only yields potential for reduced fluoroscopy dose in and increased safety of established procedures, but it also allows for the development of altogether new procedures.