This chapter concentrates on recent changes in our understanding of parathyroid disease and technology, their affect on parathyroid surgery and the ways surgical techniques have contributed to the success of minimally invasive approaches. When vitamin D deficiency is present, it should be corrected and the tests repeated. While many clinicians routinely refer patients under the age of 30 years for gene testing, expecting to detect a small number of genetic syndromes, there is no evidence at present to support this practice. Surgery for lithium-induced HPT should be restricted to those with adenomatous disease diagnosed by concordant preoperative imaging. Methylene blue cannot be recommended because of the risk of toxic encephalopathy. Tissue aspirates also have the advantage of no biopsy being required and multiple samples can be taken to help identify ectopic tissue and differentiate thyroid nodules and lymph nodes, without overburdening the histopathologists or risking permanent hypoparathyroidism. Endoscopic techniques have been shown to be safe but the advantage is minimal. After local or en bloc resection, once a patient develops a recurrence, cure is not possible. Cryopreserved tissue could be discarded after two years, so that maintaining a tissue bank would become less expensive. Given the limited success of cryopreservation there is also a case for limiting its use to patients with primary multigland disease or not using it at all. Hypocalcemia resulting from permanent hypoparathyroidism requires specialist management with at least yearly urine calcium measurements and vitamin D dose adjustment accordingly.