A chorioretinal biopsy was obtained from a patient with subretinal fibrosis and chronic uveitis. The biopsy specimen was analyzed by conventional light and electron microscopy and by immunohistochemical methods. These demonstrated a markedly inflamed choroid with a predominance of B cells and plasma cells. Complement and IgG were deposited above Bruch's membrane. The subretinal fibrosis tissue contained islands of cells with retinal pigment epithelial characteristics; however, some of these cells demonstrated surface determinants of Müller cells. There were no circulating antiretinal antibodies detected nor could virus be cultured from the biopsy specimen. The clinical appearance of this entity is distinctive and consists of a chronic posterior uveitis with transient initial yellow-white deep retinal lesions and the later development of large white subretinal fibrotic areas. The EOG is markedly decreased. We hypothesize that the immunologic events involved in this entity include antibody production with immunoglobulin and complement deposition leading to retinal and retinal pigment epithelial destruction and a subretinal fibrous proliferation.