The intraoperative injury of the external branch of the Superior Laryngeal Nerve (SLN) is a disregarded complication of thyroid surgery that becomes a serious one for particular professional groups. The Authors retrospectively evaluate 124 cases of total thyroidectomies performed by the same surgeon from 1999 to 2002. Clinically evaluated SLN lesions (hypomobility of the vocal cord) was registered in six patients (4.8%). Routine identification of SLN and meticulous dissection of the superior thyroid vessels must be the technical benchmark to avoid nerve injury, even if bulky disease, anatomic variations and previous surgery may increase the chance of nerve damaging.