A clinical case of unilateral capsular exfoliation syndrome was observed in the previously traumatized eye of a 22-year-old man with a drawn-down pupil. The distribution of material corresponded to the folds of the inner surface of contiguous iris. The periphery of the lens was free of deposits, as far as could be seen. These findings contradict previous theories on the source of the fibrillar material from the lens epithelium and indicate that it is derived from the iris pigment epithelium and not from within the lens capsule, although there is no question that a similar process involves the peripheral lens epithelium and capsule, the products of which probably do not reach the lens surface.