Standard bilateral neck exploration, in primary hyperparathyroidism (pHPT), has been challenged by the general trend toward less invasive surgery. The development of more reliable preoperative imaging techniques ? such as sestamibi scanning, which localizes adenoma in 80-90% of patients ? allows unilateral exploration. Minimally Invasive Radioguided Parathyroidectomy (MIRP) combines parathyroid scanning, using 99mTc-sestamibi, with a hand-held intraoperative detector that guides the surgeon to the adenoma. We report a case of pHPT in a patient with positive sestamibi scanning treated with this surgical procedure. The patient was a 45 year old woman. The diagnosis of pHPT was based on hypercalcemia associated with elevated intact parathyroid hormone levels and the demonstration of a solitary adenoma both on 99mTc-sestamibi scintigraphy. The positive scan for a single adenoma s the cause of primary hyperthyroidism, together with a normal thyroid pattern, candidates the patient for surgery. Tc-sestamibi radioisotope (10 milliCurie) was administrated 60 minutes preoperatively. Using an incision of 2 cm the dissection down the adenoma was guided by a hand-held probe. MIRP is indicated on a clearly positive parathyroid sestamibi scan, results in excellent cure rates for pHPT, helps in detecting aberrant parathyroid adenomas, can be performed safely and reduces operative and hospital charges by almost 50%.