Primary hyperparathyroidism (PHPT) is a biochemical syndrome caused by the inappropriate or unregulated overproduction of parathyroid hormone, leading to hypercalcaemia. It was previously considered a relatively rare disorder, with clinical manifestations dominated by renal and/or bone disease. However, in modern times the diagnosis is most frequently recognized coincidentally on biochemical testing in patients evaluated for unrelated complaints. Parathyroidectomy is the only curative treatment for PHPT, with improved outcomes in symptomatic patients following this procedure. However, surgical intervention in patients with no clear clinical features remains controversial. The National Institutes for Health (NIH) have developed consensus guidelines giving specific indications for when surgery is recommended in patients with asymptomatic PHPT. This article examines the impact of treatment on asymptomatic PHPT, focusing on bone disease, neurocognitive function, quality of life, cardiovascular disease and mortality. Medical treatment options, including bisphosphonates and cinacalcet, are also discussed.