The advent of high-resolution ultrasound scanners has made possible the clear depiction of normal peripheral nerves. Ultrasound offers many advantages over magnetic resonance imaging (MRI) with respect to imaging of the peripheral nerves. It is faster, less expensive, and offers significantly higher spatial resolution. It also offers the ability to perform a dynamic study to assess the relationships of a nerve to surrounding structures, such as muscles, tendons, and ligaments. Comparison with the contralateral asymptomatic side is also a significant advantage in using ultrasound for the demonstration of peripheral nerves.