Mucosal perforation during Fredet-Ramstedt pyloromyotomy is the cause of unnecessary morbidity and death if unrecognized. Previously, a variety of closure have been advocated. In 1,777 cases there has been 42 (2.3%) intraoperative perforations. One unrecognized perforation led to a postoperative death. Closure of a mucosal tear is accomplished safely by a simplified suture technique without prolonged convalescence or death.