Intraocular lenses are becoming increasingly common, yet many emergency physicians are unaware of their potential complications. The case of a 59-year-old man whose anterior chamber lens occluded the pupil, resulting in acute glaucoma with an intraocular pressure exceeding 65 mm Hg, is presented. He was treated successfully with medical therapy and laser iridotomy. A review of this condition, treatment, and prognosis is presented. The emergency treatment of pupillary block glaucoma differs from that of "classic" acute closed-angle glaucoma.