Résumé : Introduction: One anastomosis gastric bypass (OAGB) has become one of the most commonly performed gastric bypass procedures in some countries. Objectives: To assess how surgeons viewed the OAGB, perceptions, indications, techniques, and outcomes, as well as the incidence of short- and long-term complications and how they were managed worldwide. Methods: A questionnaire was sent to all IFSO members in all 5 chapters to study the pattern of practice and outcomes of OAGB. Results: Seven hundred and forty-two surgeons responded. The most commonly performed procedures were sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and OAGB. Preoperatively, 70% of the surgeons performed endoscopy routinely. In regards to weight loss, 83% (570 surgeons) responded that OAGB produces better weight loss than SG, and 49% (342 surgeons) responded that OAGB produces better weight loss than RYGB. The most common length of the biliopancreatic limb (BPL) utilized was 200 cm. Sixty-seven percent of surgeons did not measure the total length of the small bowel. In patients with reflux disease and history of smoking, 53% and 22% of surgeons respectively still offered OAGB as a treatment option. Postoperatively, leak was documented in 963 patients, and it was the leading cause for mortality. Leak management was conservative in 35%. Conversion to RYGB was performed in 31%. In 16% the anastomosis was reinforced, 6% of the patients were reversed, and other procedures were performed in 12%. Revision of OAGB for malnutrition/steatorrhea or severe bile reflux was reported at least once by 37% and 45% of surgeons, respectively (200 cm was the most commonly encountered biliopancreatic limb BPL in those revised for malnutrition). Most common strategy for revision was conversion to RYGB (43%), reversal to normal anatomy (32%), shortening of the BPL (20%), and conversion to SG (5%). Nevertheless, 5 out of 98 mortalities (5%) were due to liver failure/malnutrition. Conclusion: There are infrequent but potentially severe specific complications including malnutrition, liver failure, and bile reflux that may require surgical correction after OAGB.