CMV is a common virus, which can cause blindness and death in AIDS patients. Previous studies demonstrate that foscarnet has been effective in both AIDS and non-AIDS patients with CMV infection. Although treatment with ganciclovir (DHPG) is also effective, a significant toxicity leading to dose-limiting neutropenia (low white blood cell count) in one third of treated patients has been associated with the drug. Based on the serious nature of CMV retinitis and the lack of alternative drug therapies for DHPG-sensitive patients, the present study will evaluate the safety and efficacy of intravenous (IV) foscarnet in AIDS patients with CMV retinitis.