Cataract removal with implantation of an intraocular lens (IOL) was performed in 36 cases of Fuchs' unilateral syndrome. --Intracapsular technique with anterior chamber IOL: 3 cases. --Extracapsular with IOL: 33 cases: Binkorst four loops sutured to the iris: 10 cases; posterior chamber in the sulcus: 12 cases; posterior chamber in the bag: 11 cases. The operative difficulties in such an indication consist in the constant hemorrhaging in the anterior chamber, the poor dilatation and the fragility of the zonule. Inflammatory reactions during the immediate post-operative follow up are frequently observed (22.2%) with pupillary deformations and Irvine Gass syndrome as complications. Glaucoma is a worrisome complication in its unusual frequency and by the poor results obtained by surgical treatment, but it does not seem to be directly related to the operation on the cataract. The complications which appear to relate directly to the implantation are represented above all by the risk in the long time, of lack of IOL transparency caused by the precipitates, and the aggravation of secondary vitreal disorders relating to recurrent cyclitis which is more frequent than in cases without implantation. The type of IOL implanted appears to have played no role on surgical results. Functional results were relatively good (83.3% having visual acuity superior or equal to 5/10). The restoration of satisfactory binocular vision justifies the risks of IOL implantation in cases of Fuchs' unilateral syndrome, but it is important to be forewarned of such an procedure risks.