Accelerated atherosclerosis is known to occur in diabetes mellitus, but the exact mechanisms for this adverse consequence are unknown. Prospective determination of each patient's state of atherosclerosis coupled with serial comparisons between patients could be used to clarify relationships between insulin levels and growth rates of atherosclerotic lesions. Noninvasive measurements of atherosclerosis that are now feasible are phonoangiography, continuous-wave and pulsed Doppler ultrasound imaging, reflected beta-mode ultrasound imaging, computed axial tomography, and nuclear magnetic resonance imaging. An interesting new application of ultrasound beta-mode imaging for the estimation of localized arterial wall stiffness is described.