Ultrasound has been used with varying success to localise parathyroid adenomas pre-operatively. We have reviewed 61 patients with pre-operative contact-scanning grey-scale parathyroid ultrasonography and subsequent surgical exploration of all four parathyroid glands. Diagnostic accuracy was 91% considering glands examined and 63% considering patients examined. There was one false positive diagnosis. False negative diagnoses (17 adenomas and five ectopic mediastinal tumours) were mainly due to upper pole adenomas, adenomas less than 10 mm X 7 mm in size and ectopic mediastinal adenomas. Static grey-scale ultrasonography is adequate for the pre-operative localisation of parathyroid adenomas, especially when high-resolution technique is not available. In fact, the overall accuracy is comparable to the recently reported diagnostic accuracy rates with high-resolution real-time systems.