Electrodiagnostic studies are often at the centre of diagnostic strategies in neuromuscular disorders. The basic electrophysiological techniques commonly used are focused on documenting sufficient proof of dysfunction emanating from different parts of the peripheral nervous system: peripheral motor neuron, nerve root, plexus and peripheral nerve, neuromuscular junction, and skeletal muscle. In short, dedicated nerve conduction studies and needle myography or a combination of these may be needed to help accurately identify the site and nature of the neuromuscular disorder (Fig. 4.1A–C). Appropriate and standardized instrumentation, including control of temperature and uniform sampling, is essential for meaningful interpretation. The electrodiagnostic techniques aligned with the main anatomical correlates underlying different neuromuscular disorders are discussed in this chapter.