Temporal arteritis (granulomatous inflammation) usually involves the temporal and ophthalmic arteries, but may be part of a more widespread inflammation of the medium and large vessels. The patient usually presents with an associated group of constitutional symptoms (fever, malaise, anorexia, weight loss, anemia) and rheumatic complaints (polymyalgia rheumatic complaints (polymyalgia rheumatica). The diagnosis should be considered in any patient over 55 years old in whom these symptoms develop or in whom there is evidence of recent onset of headache, visual loss of localized arterial involvement. The diagnosis is also to be considered when the erythrocyte sedimentation rate is over 50 mm/hr, and the presence of arteritis is confirmed by temporalartery biopsy findings. Visual loss may occur in 50 percent of affected patients; other serious complications are less common. A strong clinical suspicion of temporal arteritis will permit diagnosis of the more uncommon and atypical presentations of the syndrome. Although cases of temporal arteritis may be self-limited, treatment is imperative because of the threat of blindness. Patients respond well to steroid (prednisone) therapy, which should be maintained for a prolonged period.