The recent use of ultrasound-guided techniques to facilitate the placement of regional anesthesia blocks is the result of a search for more consistent and safer methods of nerve localization. Ultrasound guidance has been found to be helpful during the performance of brachial plexus anesthesia, particularly since advanced equipment with compound imaging and high-resolution probes (>10 MHz) have become available. In this article we describe an approach to the performance of ultrasound-guided interscalene brachial plexus blockade. Our technique begins with the scanning of the lateral neck with the probe in an axial oblique angle. In this view we obtain a short axis or transverse image of the nerve roots between the anterior and the middle scalene muscles. We also identify important vascular structures such as the carotid artery, internal jugular vein, and vertebral artery. Once the roots are identified, a needle is inserted following the long axis of the ultrasound probe, under real-time imaging, until the needle tip is visualized to lie in close proximity with one or more nerve roots. During injection of the local anesthetic, one can verify proper spread of the solution via real-time imaging. However, further research is needed to ascertain the impact of ultrasound guidance on block success rates and safety.