A variety of new devices in the field of intravascular ultrasound imaging are being designed and tested. Mechanical intravascular ultrasound (IVUS) devices with rotating transducers have been developed that allow transducer pullback with integrated longitudinal 2-dimensional displays. Recent advances in the area of imaging include (1) solid-state systems that combine ultrasound with balloon and stent placement; (2) combined imaging atherectomy devices; (3) imaging cores or guidewires; (4) forward-looking devices; (5) 3-dimensional reconstruction techniques; (6) high-frequency imaging; and (7) improved methods for characterizing tissue. Other promising approaches include magnetic resonance imaging, thermography, and optical coherence tomography. An important goal for long-term technologic improvement is visualization of lipid accumulations and fibrous caps during their early stages of development.