Ten year follow-up examinations were obtained on 72 cases having pars plana vitrectomies for diabetic retinopathy complications from 1970 to 1973. Forty-two percent of the cases maintained 6/60 or better visual acuities through the tenth year. The visual results were quite stable, with 53% of the cases having the same or better visual acuities at ten years compared with six months. Neovascular glaucoma developed in 11 eyes, usually during the first six months, and open-angle glaucoma developed in 16 eyes, usually after the five-year follow-up examination. Both types of glaucoma occurred almost exclusively in aphakic eyes. Cataracts developed in 75% of retained clear lenses. The vitreous cavities remained clear in 67% of the eyes, and the maculas were attached in 65% of the eyes 10 years following vitrectomy. Fundus neovascularization did not recur.