Conventional brachial plexus block techniques are performed without visual guidance and are highly dependent on surface anatomical landmarks for localization of neural structures. It is, therefore, not surprising that a reported failure rate of up to 20% occurs because of incorrect needle and/or local anesthetic placement. Multiple trial and error attempts at needle placement lead to operator frustration, unwarranted patient pain and time delay in the operating room. Imaging technology such as MRI and CT scan can successfully localize neural structures. However, ultrasound is likely the most practical imaging tool for assisting nerve blocks as it is portable, moderately priced and non-invasive without radiation risk.