We have developed a reproducible model of traction retinal detachment in the rhesus monkey secondary to a penetrating eye injury. The model is characterized histologically by intravitreal fibroblastic proliferation and by epiretinal and by retroretinal membranes. Cells proliferating within the vitreous and in the epiretinal membranes have the ultrastructural characteristics of myofibroblasts. The presence of these contractile cells suggests that vitreous traction and the contraction of epiretinal membranes may be cell mediated. Our findings suggest that the pathophysiology of traction retinal detachment has many features in common with the normal process of wound healing and in particular with the mechanisms responsible for wound contraction and cicatrization.