Hypercalcaemia is most commonly caused by primary hyperparathyroidism (PHPT) or malignancy. PHPT is common, affects more females than males, and is usually due to a solitary parathyroid adenoma. The usual presentation now is asymptomatic and incidentally picked up on blood testing. The only curative treatment is parathyroidectomy. In 2009 the Third International Workshop on the Management of Asymptomatic Primary Hyperparathyroidism updated their guidance on management of asymptomatic PHPT. They recommend surgery in: all symptomatic patients; asymptomatic patients with hypercalcaemia greater than 0.25 mmol/litre above the upper limit of reference range, evidence of end-organ damage, including impaired renal function, and reduced bone mineral density; and patients under 50 years old in whom disease is more likely to progress. In other patients, conservative management is an acceptable management strategy so long as they can be monitored regularly. However, defining ‘asymptomatic’ is not always clear and there is growing awareness of the prevalence of reduced quality-of-life scores among patients with asymptomatic PHPT. Therefore, careful clinical decision-making is required in this group of patients. Medical management of PHPT is generally unsatisfactory although there is some evidence that alendronate may increase bone mineral density in PHPT and there are preliminary data supporting a possible role for the calcimimetic, cinacalcet.