The purpose of this guideline is to assist specialists in Nuclear Medicine and Radionuclide Radiology in recommending, performing, interpreting and reporting the results of Parathyroid Scintigraphy. This guideline will assist individual departments to formulate their own local protocols. This does not aim to be prescriptive regarding technical aspects of individual camera acquisitions which need to be developed in conjunction with the local medical physics expert. These guidelines pertain only to adult patients. There are numerous techniques for localizing Parathyroid adenomas. This guideline will describe the use of 99mTc-sestamibi dual phase imaging which may be used alone or in combination with other modalities.