We examined 91 patients with Best's dystrophy and followed 54 affected individuals for five years. Most eyes with normal maculas, minimal pigment epithelial changes, atrophic maculae, or fibrous macular scars did not change stage. Eyes with vitelliform or pseudohypopyon lesions progressed to later atrophic macular stages. Visual acuity decreased after age 40 and was worse for patients with atrophic maculas and fibrous scars. Nineteen percent of patients with atrophic maculas or fibrous scars who were followed for 8 to 10 years were the only patients to lose vision.