The major cause of peritonitis in bariatric surgery is leakage of GI contents, which can have a catastrophic outcome for the bariatric patient. To resolve this serious problem, the surgeon must act quickly. This paper describes a 27-year-old female after gastric bypass with disruption of the gastroenterostomy and severe contamination and peritonitis. Closure of the anastomotic leak, drainage, and gastrostomy in the bypassed stomach were performed, but the abdomen could not be closed, due to dilated bowel and the intra-abdominal edema with the sepsis. Temporary laparostomy closure was performed; a plastic sheet with an overlying mesh was sutured to the fascial margins. Planned multiple reoperations permitted removal of necrotic and infected debris, with progressive approximation and ultimate closure of the fascia. This treatment resulted in a successful outcome for the patient.