The International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) is a federation composed of national associations of bariatric surgeons. Currently, there are 51 official member societies of IFSO. There are also individual members from countries that thus far have not formed a national association. IFSO has been mainly a scientific organization, bringing together surgeons and allied health professionals, such as nurse practitioners, dieticians, nutritionists, psychologists, internists and anesthesiologists, involved in the treatment of morbidly obese patients, but in the upcoming years, IFSO will maintain and extend its roll in the challenge of bariatric surgery. IFSO is growing into a professional organization, with the goal to support its members in aspects directly related to their profession. IFSO's main activity is currently the organization of the yearly World Congress, which provides a forum to exchange knowledge on surgical treatment of severely obese patients, to present new techniques, research and concepts, and to meet the experts in the field. An international obesity surgery meeting was held annually in various countries throughout the world under the leadership of Nicola Scopinaro. At the Stockholm meeting in 1995, the International Federation for the Surgery of Obesity (IFSO) was formed. The first International Congress of IFSO was held in Prague in 1996, followed by Cancun in 1997, Bruges in 1998, Salzburg in 1999 and Genoa in 2000. The first President was Nicola Scopinaro of Italy, followed by George Cowan of U.S.A. and Emanuel Hell of Austria. IFSO has also produced a number of guidelines, such as selection criteria for patients, minimal requirements for bariatric surgeons, and Statements on morbid obesity, its treatment, and innovation and is committed to the creation of a system for accreditation of individual surgeons and bariatric centers around the globe . The main goal of IFSO is optimisation of the treatment of severely obese patients.