Our objective was to develop an operation for morbid obesity that would be simple, safe, and effective and yet have few long-term adverse physiologic effects. Vertical gastroplasty was chosen. A small proximal gastric pouch was fashioned by stapling vertically beginning 5 cm distal to the cardia along the lesser curvature of the stomach and ending just lateral to the esophagogastric junction along the greater curvature. A 1.1-cm channel through the staple line was left near the lesser curvature of the stomach. No gastric incisions, enterostomies, or anastomoses were necessary. Among 57 patients (with a mean +/- SEM preoperative weight of 136 +/- 4.5 kg) operated on since January 1981, no deaths occurred and no gastric reoperations were done. The hospital stay was short (mean, 9 days). In 32 patients who were followed up for 1 year or longer, the mean percentage of excess weight lost was 39% at 6 months, 43% at 12 months, and 34% at 24 months. Two patients had disruption of the staple line and regained weight by 24 months postoperatively. Channel stenosis occurred within 6 months after operation in seven patients, all of whom were managed successfully with endoscopic dilation. We conclude that vertical gastroplasty is a simple, safe operation for morbid obesity with few adverse sequelae, but the percentage of excess weight lost during a 1- to 4-year follow-up exceeded 50% in only 31% of our patients.