Acute retinal necrosis (ARN) is generally a progressive retinitis, often complicated by retinal detachment and a poor visual outcome. A series of 12 consecutive patients (13 eyes) with ARN is reported. All patients were examined early, with a limited extent of disease (in 77% of the eyes, less than 25% of retina involved). Patients were treated with high-dose intravenous acyclovir (10 mg/kg every 8 hours) and laser photocoagulation. During a follow-up period of 3 to 21 months, only 1 patient developed a rhegmatogenous retinal detachment resulting in visual loss. No patients developed bilateral disease once intravenous antiviral therapy was begun. Final visual acuity was 20/40 or better in 6 eyes (46%), and 20/400 or better in 12 eyes (92%). Two patients were examined within 6 weeks of extracapsular cataract extraction with intraocular lens implantation. In the majority of the cases, clinical findings were limited to several quadrants of the peripheral retina. Eyes with limited disease, if aggressively treated, have a relatively good visual prognosis.