Fibrous membrane formation on the anterior surface of an intraocular lens with occlusion of the pupil was noted in five patients having phacoemulsification and one patient having planned extracapsular cataract extraction. Initial onset of pain and decreased vision ranged from eight to 36 postoperative days. Since these patients did not respond fully to steroid therapy, the neodymium:YAG laser was used to disrupt the fibrinous membrane which occluded the pupil. In all but one case, the fibrinous reaction responded to laser therapy. Generally, less energy was required when laser therapy was initiated early in the treatment plan.