Diagnosis and treatment of primary hyperparathyroidism has changed substantially during recent years. Routine serum calcium measurements and development of specific as well as sensitive PTH assays made primary hyperparathyroidism the most prevalent diagnosis of hypercalcaemia in the normal population. With increasing numbers of asymptomatic patients secondary complications are reduced but the demands made on surgeon's technical skill are much higher. In view of our experience in 329 patients with primary hyperparathyroidism during the last six years and a success rate of 98% we refrain from any localisation technique and advocate visualisation of all four glands.