Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are clinical diagnoses without “gold standard” serological or histological tests, excluding temporal artery biopsy for GCA. Further, other conditions may mimic GCA and PMR. Treatment with 10–20 mg of prednisolone daily is suggested for PMR or 40–60 mg daily for GCA when temporal arteritis is suspected. This ocular involvement of GCA should be treated as a medical emergency to prevent possible blindness and steroids should be commenced immediately. There are no absolute guidelines as to the dose or duration of administration; the therapeutics of treating this condition and the rate of reduction of prednisolone should be adjusted depending on the individual’s response and with consideration of the multiple risks of high-dose and long-term glucocorticoids. Optimal management may need to consider the role of low-dose aspirin in reducing complications. Clinicians should also be aware of studies that indicate an increased incidence of large-artery complications with GCA. This clinical area requires further research through future development of radiological imaging to aid the diagnosis and produce a clearer consensus relating to diagnosis and treatment.