Ischemic optic neuropathy, in its arteritic and idiopathic varieties, presents both diagnostic and therapeutic challenges to the clinician, specifically: the role of temporal artery biopsy in management of giant cell arteritis; the preferred treatment regimen for giant cell arteritis, including decisions to begin tapering therapy and stopping therapy; action to take if major steroid complications arise while the disease is still active; distinguishing anterior ischemic optic neuropathy from idiopathic optic neuritis; whether cerebral arteriography is indicated in the assessment of idiopathic ischemic optic neuropathy; and whether steroid therapy is of any value in the treatment of idiopathic ischemic optic neuropathy.