Cytomegalovirus (CMV) retinitis is the most common ocular opportunistic infection in patients with acquired immunodeficiency syndrome (AIDS). The disease is inexorably progressive when untreated, making early detection and prompt treatment essential for preservation of functional vision. The retinitis tends to be unilateral at presentation but often becomes bilateral as it progresses. Lesions may be unifocal or multifocal and may appear in the posterior retina or peripheral retina. Primary ophthalmoscopic features of CMV retinitis include white granular zones of retinal necrosis, variable degrees of associated hemorrhage, and low-grade iritis and vitritis. Differential diagnosis is aided by characteristic features of CMV retinitis and other AIDS-related retinopathies. Initial treatment with ganciclovir or foscarnet has been found to stabilize retinitis, and maintenance therapy with either has been shown to prolong the time to retinitis progression. Further studies should help to determine the optimal approach to treatment of the disease.