Giant cell arteritis (GCA) and Takayasu's arteritis (TA) are characterised by systemic inflammation and critical ischaemia. GCA is a medical emergency. Neuro-ophthalmic complications occur early, with permanent vision loss in up to a fifth of patients, resulting mainly from failure of prompt recognition and treatment. Diagnosis of large vessel vasculitis is often delayed due to poor recognition of early, often non-specific symptoms. Laboratory inflammatory markers are often discordant with disease activity. Modern imaging techniques show promise in diagnosis and disease monitoring, improving our understanding of major artery involvement in large vessel vasculitis. However, in practice, their role is still unclear. The mainstay of therapy remains corticosteroids. Experience using conventional disease-modifying drugs is mixed, and biological therapies require further evaluation for their steroid-sparing potential.