More than 95% of patients with primary hyperparathyroidism have been treated with bilateral neck exploration by experienced surgeons. This procedure has been performed without employing preoperative localization tests or specialized techniques of intraoperative measurement. A renewed interest in unilateral neck exploration for primary hyperparathyroidism emerged (in three developments), in an attempt to maintain the excellent cure rate and to minimize the invasiveness of the procedure. The first development was the introduction of sestamibi scintigrams as a new preoperative localization technique and intraoperative nuclear mapping with a hand-held gamma probe. The localization of adenomas using this technique was much more accurate than that of previous localization studies, allowing unilateral procedures to become feasible. Sestamibi guidance enables parathyroidectomies to be performed much more rapidly through a significantly less invasive dissection. Secondly, the intraoperative quick parathyroid hormone assay allows the confirmation of removal of the parathyroid mass. The third development was endoscopic parathyroidectomy. Various approaches have been shown to be technically feasible, including endoscopic procedures that rely on CO2 insufflation to create a working space or video-assisted procedures in which the working space is maintained through conventional external retraction. Given the safety and high success rate of the standard exploration, the potential advantages of these new strategies include decreased operating time, local or regional anaesthesia rather then general anaesthesia, and smaller incisions.