As long as the cause of peptic ulceration remains unknown, which unfortunately will probably be a long time, the methods used for its correction will vary and so will the results. This variation will depend on the knowledge and experience of the internist and the surgeon, and on the response of the patient to the method used to reduce gastrospasm by decreasing the quantity and concentration of hydrochloric acid secreted by the stomach. Variation also depends on the ability to develop the patient's insight and knowledge of the association of peptic ulcer with nervous and emotional disturbances. Of even greater importance is the response of the individual patient's gastrointestinal mucosa to the digestive action of gastric secretion.Only about 13% of the patients suffering from duodenal ulcer who have come to the Mayo Clinic in recent years have required surgical treatment. These patients had complications with which we are all familiar. In these cases the internists and surgeons advised operations since medical management was no longer feasible and was likely to be followed by untoward results. The other 87% of patients with duodenal ulcer have been pro¬ vided with a medical regimen because of a short history of ulcer or no previous trial of good medical treatment and because no complications were present.The patient with gastric ulcer needs a different pro¬ gram of treatment, for gastric ulcération differs in many ways from duodenal ulcération. When operation is neces¬ sary for gastric ulcer and the ulcerating lesion is re¬ moved by partial gastrectomy, the results are excellent in practically every case, recurrent ulcération never oc¬ curs, and the operative risk is less than 2%. Obviously there is no place for vagotomy alone in the treatment of such lesions, for it leaves behind an ulcerating lesion that has a 20% chance of becoming malignant. When vagot¬ omy has been used, it has been followed by a high re¬ currence rate for benign gastric ulcération and a high incidence of troublesome digestive symptoms due to the atonie stomach, which does not empty satisfactorily. Happily, few surgeons continue to use vagotomy in the treatment of gastric ulcer.We will confine our remarks for the most part, there¬ fore, to the use of vagotomy in the treatment of duodenal ulcer and to ulcer recurring after either gastric resection or a gastroenterostomy. We will try to answer the fol¬ lowing questions and a few others that will be suggested by the discussion. 1. Will vagotomy alone cause healing of duodenal and gastric ulcers? 2. Will vagotomy added to gastroenterostomy improve the results of gastroenter¬ ostomy alone for duodenal ulcer? How do these results compare with those of gastric resection with and without vagotomy? 3. Will vagotomy alone cause healing of gastrojejunal ulcers which may follow (a) gastroenterostomy or (b) gastric resection, and in what comparative pro¬ portions? 4. Which type of treatment, vagotomy, gastric resection, or reresection, yields better functional results and lower recurrence rates in cases ...