Truncal vagotomy and posterior, no loop gastrojejunostomy is a safe and expedient procedure for chronic duodenal ulcer. A proved recurrence rate of only 1.5 per cent was noted at a mean of 10.5 years after operation in a 94 per cent follow-up study of 290 surviving patients from a consecutive series. One of the most striking features has been the identification of the relationship between age at operation and outcome. Life does, indeed, appear to begin at 40. If the decennial age groupings at operation are reviewed considering postoperative patients attaining the fifth decade of life. In the surgical treatment of chronic duodenal ulcer, the present operation is advocated for patients older than 40 years of age. It is suggested that other treatment be sought for those less than 40 years of age. If this group cannot continue with medical treatment, then a reasonable choice of operative procedure would seem to be proximal gastric vagotomy.