Since 1 October 1986, all cataract, keratoplasty and glaucoma operations have been evaluated prospectively in the Department of Ophthalmology and Eye Hospital at the University of Erlangen-Nürnberg. The medical history data and preoperative status, intraoperative details and the postoperative course are standardized and stored. For each eye, the diagnosis is made according to the system called the "Erlanger Schlüssel." The present status of the Erlanger Ophthalmological Documentation System for Cataract, Keratoplasty and Glaucoma surgery is outlined. The difficulties encountered when the project was started are pointed out. The importance of electronic data processing in research, teaching and patient care is discussed.