Diagnosis and treatment of the immobile or hypomobile vocal fold are challenging for the otolaryngologist. True paralysis and paresis result from vocal fold denervation secondary to injury to the laryngeal or vagus nerve. Vocal fold paresis or paralysis may be unilateral or bilateral, central or peripheral, and it may involve the recurrent laryngeal nerve, superior laryngeal nerve, or both. The physician’s first responsibility in any case of vocal fold paresis or paralysis is to confirm the diagnosis and be certain that the laryngeal motion impairment is not caused by arytenoid cartilage dislocation or subluxation, cricoarytenoid arthritis or ankylosis, neoplasm, or other mechanical causes. Strobovideolaryngoscopy, endoscopy, radiologic and laboratory studies, and electromyography are all useful diagnostic tools.