In a group of 709 individuals with diabetes diagnosed prior to age 50 and followed for five to thirteen years a strong inverse relationship was demonstrated between the severity of the retinopathy at the initial visit and survival. Survival in patients with no retinopathy or with microaneurysms only was little different from that of the general population (five-year rate .99, SE .01). The five-year survival rate for patients with more severe nonproliferative retinopathy, characterized by the presence of hemorrhages and/or exudates, but without new vessels or vitreous hemorrhage (B2), was .81 (SE .04), and that for patients with proliferative retinopathy (PDR) was .56 (SE .03). After adjustment for age at diagnosis of diabetes, duration of diabetes and sex, the differences in survival between these three groups were highly statistically significant. Impairment of visual acuity was also shown to be inversely related to survival. The five-year survival rate for patients with visual acuity of 20/200 or worse in each eye was .42 (SE .05). In patients with B2 retinopathy there was a weak but statistically significant trend towards decreasing survival with increasing duration of diabetes. In patients with PDR survival decreased with increasing duration up to 20 years, but then improved for patients with 20 years or more of diabetes.