1. Types of bariatric procedures and their fundaments 2. Selection of patients for malabsorptive surgery. Indications and contraindications 3. Psychological evaluation of candidates for a malabsorptive surgery 4. Special anesthetic considerations for patients planned for a malabsorptive surgery 5. Nutritional optimization prior to malabsorptive surgery 6. Biliopancreatic diversion 7. Duodenal switch 8. One anastomosis gastric bypass 9. Single-anastomosis duodeno-ileal bypass with sleeve (SADI-s) 10. Revisional surgery 11. Endobarrier 12. Other techniques: SAGIS/SASI, Bipartición intestinal 13. Early postoperative complications 14. Weight loss and remission of comorbidities 15. Nutritional sequelae 16. Specific supplementation requirements 17. Long term effects and complications of malabsorptive techniques 18. Impact of physical activity pre- and postoperatively 19. ERAS protocols 20. Personal experience of a bariatric surgeon and simultaneously patient undergoing a malabsorptive procedure 21. Future basic research lines on malabsorptive procedures 22. Economic impact of malabsorptive procedures 23. Quality of life of patients undergoing malabsorptive techniques