Several techniques may be used to localize target nerves. The classic approach uses anatomical landmarks, tactile feedback from fascial clicks, and elicited paresthesias to guide needle advancement and injection. Nerve stimulator–guided techniques allow the operator to estimate the distance of the needle tip from the target nerve based on the magnitude of current required to elicit the desired motor response. Ultrasound-guided techniques allow for real-time visualization of the needle tip, relevant anatomy, and local anesthetic spread and have become widely used in recent years. Studies have shown that the use of ultrasound may reduce block performance time, number of needle passes, and volume of local anesthetic required for successful block and may also reduce the incidence of vascular puncture. Nevertheless, complications such as intravascular and intraneural injection have occurred even with the use of ultrasound.