Normocalcemic hyperparathyroidism (NCHPT) is characterized by the co-existence of persistently normal serum calcium levels and elevated serum parathyroid hormone (PTH) levels in the absence of an identifiable cause for secondary hyperparathyroidism. NCHPT is a rare condition and has historically often been misapplied due to a lack of clear diagnostic criteria. The pathophysiology of NCHPT is unclear, and while some cases do ultimately progress to become classical primary hyperparathyroidism, many do not. Patients are often diagnosed with NCHPT during work-up for kidney stones or bone mineral disorders. This has led to conflicting evidence regarding the consequences of untreated NCHPT, with specialty referral centers reporting a high rate of associated morbidity and population-based studies showing very little. In appropriately selected patients, surgery can be successful in restoring calcium and PTH to normal levels. However, surgery can be challenging in the setting of NCHPT as there is a high rate of multi-gland disease, and abnormal glands are often smaller than those found in classical PHPT. Intraoperative parathyroid hormone testing is useful in guiding the extent of surgery.