Bariatric surgery is an elective intervention, which is also performed in patients with additional risk factors, e.g. elderly patients over 65 years old, in patients suffering from relevant comorbidities and in patients with a body mass index (BMI) greater than 60 kg/m(2). To reduce the perioperative risks comorbidities require optimal adjustment. Specialized centers have reported complication rates below 1 %. Besides leakage, bleeding is the most common surgical complication in bariatric interventions. Bleeding complications occur in up to 4 % of cases but are much more common in redo surgery. For the management of bleeding, the same general rules apply as those for abdominal surgery and at the end of an operation, all bleeding must be under control. To avoid bleeding, sealing devices are widely used during tissue dissection. Stapler line bleeding is the most common form of intraoperative and postoperative bleeding. Special stapler magazines and stapler line reinforcement materials are available to minimize stapler line bleeding. Such devices result in relevant extra costs; however, they should always be generally available and used in patients with an increased risk of bleeding or an increased intraoperative tendency to bleeding.