In 85-90% of the cases primary parathyroidism is caused by a single adenoma. In experienced hands the success of the standard parathyroidectomy is 95%. Recently, radioguided parathyroidectomy offers an alternative to standard parathyroidectomy. The sensitivity of the sestamibi scintigraphy is 90%for single adenomas. In Hacettepe University Hospitals sestamibi scintigraphy is performed successfully. In 2001, the arrival of a hand held gamma probe to our hospital enabled us to perform radioguided surgery. Here, we describe first nine cases treated by radioguided parathyroidectomy. In all of the cases the pathological parathyroid tissue could be localized. In eight of nine cases preoperative sestamibi scan localized the parathyroid tissue. As a result of our study, one can say that radioguided surgery facilitates recurrent and difficult cases. It’s obvious that the intraoperative use of gamma probe can decrease the incidence of recurrent nerve damage. For these reasons, radioguided surgery may be appropriate for selected cases. [Turk J Cancer 2007;37(4):137-142]