The term proliferative vitreoretinopathy (PVR) is proposed as a designation for the clinical condition previously known variously as massive vitreous retraction, massive preretinal retraction, or massive periretinal proliferation. This is an abnormality in which rhegmatogenous retinal detachment is complicated by proliferation of membranes on both surfaces of the detached retina and on the posterior surface of the detached vitreous gel. The new classification subdivides PVR into four stages: A, minimal; B, moderate; C, marked; and D, massive. The extent of the fixed retinal folds is subdivided to indicate the number of involved quadrants. The degree of retinal shrinkage into a funnel-like configuration is subdivided into three grades.