Surgery is the only curative treatment for primary hyperparathyroidism. Several intraoperative adjuncts have been developed to facilitate parathyroidectomy to achieve a successful outcome. These include sestamibi-SPECT scanning, cervical ultrasound, 4D-CT scans, and intraoperative parathyroid hormone monitoring. One technology often overlooked is radioguided parathyroidectomy. Radioguided parathyroidectomy is closely related to other radioguided techniques already in use for breast cancer, malignant melanoma, thyroid cancer, and colon cancer. A radiotracer is administered, which accumulates preferentially in the targeted tissue. Radioguided techniques localize specifc tissue through the use of radioactivity, theoretically minimizing dissection and decreasing overall operative time. The radiotracer utilized for radioguided parathyroidectomy is technetium 99mTc–sestamibi, which is the same compound used for preoperative parathyroid imaging. Its use is based upon the principle that enlarged, hypercellular parathyroid glands contain an increased number of mitochondria, and these mitochondria take up and retain 99mTc– sestamibi longer than surrounding tissues. Thus, the abnormal parathyroid becomes “hot” relative to surrounding structures. A hand-held gamma probe can then be utilized to detect the enlarged parathyroid gland. Once resected, the parathyroid gland can be assessed ex vivo for its radioguided counts. The counts are then used to determine if the gland is abnormal.