Hyperparathyroidism is a common clinical condition most often caused by single or multiple adenomas and less commonly by gland hy-perplasia; parathyroid carcinoma is a rare cause of hyperparathyroidism. Experienced surgeons may cure 95% of patients with hyperparathyroidism without the need for imaging guidance [1]. When hyperparathyroidism recurs or persists after surgery, surgical cure rates fall to 60% if imaging guidance is not used. Noninvasive methods used to evaluate patients with hyperparathyroidism include sonography, CT, scintigraphy, and MR imaging. A single cross-sectional study may be used to localize the side of hyper-functioning parathyroid tissue before cervical exploration for patients initially diagnosed with hyperparathyroidism. For patients with recurrent or persistent hyperparathyroidism, a combination of noninvasive imaging methods, often an anatomic method such as MR imaging and a functional method such as 99mTc sestamibi scintigraphy, are used. Familiarity with the various imaging appearances of hyperfunctioning parathyroid tissue is required for an accurate diagnosis.