Guidelines for a highly effective radical treatment protocol of thyroid cancer are based on its histopathological classification. The bases are total thyroidectomy, including the central lymph node compartment parathyroidal and paratracheal, extended to uni- or bilateral cervical lymph node dissection in case of clinical manifestation or very advanced tumor stage. Postoperative control or treatment by radioiodine is obligatory for all differentiated thyroid carcinoma. Reoperative surgery is useful for locoregional recurrence. Limited unilateral thyroid surgery is only justified in selected cases of primary tumors less than 1 cm diameter in a low-risk patient group.