This study is a randomized clinical trial to determine the therapeutic efficacy for the anti-viral drug foscarnet in individuals who have AIDS with non-sight-threatening cytomegalovirus retinitis. The study is active and currently accruing patients. Preliminary data on the first 9 patients has been accepted in abstract form for presentation at the V Annual International AIDS Conference in Montreal in June. This study is the only randomized trial assessing therapy for CMV retinitis. All other trials are non-comparative, which is a major scientific and regulatory problem. This study is assessing a drug which can be given concurrently with AZT. This study's importance is that it is the only comparative trial assessing treatment vs. no treatment for CMV retinitis, and it is assessing a drug that can be given concurrently with AZT.