Surgery has been the treatment of choice for many disorders of the thyroid gland, both benign and malignant, for many decades. However, surgery has not been invariable but has continued to change in accordance with research results. In benign cases, surgery has generally evolved to be as organ preserving as possible. In several instances, however, a more radical extent of resection seems justified in order to ensure that the risk of recurrence is as low as possible. For instance, total thyroidectomy may be beneficial in patients with endemic multinodular goitre or young patients with Graves' disease and accompanying cold nodules or high levels of autoantibodies. Several tools, e.g. magnifying glasses, bipolar coagulation forceps and neuromonitoring, are available to identify and preserve the recurrent laryngeal nerve and the parathyroid glands, hence keeping the morbidity at a low level. Most recently, minimally invasive surgery has been successfully used in treating both benign and malignant disorders of the thyroid gland. In the case of malignant disorders, minimally invasive surgery may become an attractive alternative to open surgery if a limited surgical extent is justified, e.g. in patients with micro-PTC (papillary thyroid carcinoma, diameter less than 1 cm). Whether a limited surgical approach is also justified in other cases, e.g. in any patient with intrathyroidal PTC or patients with micro-FTC (follicular thyroid carcinoma), remains to be shown and is the subject of ongoing investigations. One of the most intriguing recent discoveries is the identification of genotype-phenotype correlations in patients with hereditary medullary thyroid carcinoma. In these patients, the timing and extent of surgery may depend not only on the patient's age and serum levels of the tumour marker calcitonin but also on the specific germline RET proto-oncogene mutation. Surgery will certainly continue to play an important role in the treatment of thyroid diseases and may be increasingly based on individual findings instead of general recommendations.