During 7336 diagnostic and therapeutic endoscopies of the upper gastrointestinal tract 10 perforations of the esophagus were seen (0.14%). After diagnostic X-ray 5 patients were operated and 5 treated conservatively. The precondition for conservative treatment were immediate diagnosis and a covered perforation of the intrathoracal esophagus without communication to pleura or trachea. Treatment consisted in alimentary restriction, parenteral nutrition and high antibiotic therapy. One patient with a esophagotracheal fistula died under conservative treatment. He could not be operated because of advanced tumour disease. The others had an uncomplicated course and, after healing of the perforation, between the 5. and 15. day oral nutrition could be started. It is proved, that the conservative treatment of iatrogenic perforation of the esophagus is a minimal stressing and very successful therapy, if the above-mentioned conditions are followed exactly.