The chairman is an ex officio member of all committees and working groups, and he should participate in any of them. At the beginning of the establishment of the International Olympic Committee, Gu Baihe, the founder of the modern Olympic Games, put forward the president rotation system, that is, the president of the International Olympic Committee is a member of the host country of the Olympic Games and rotates every four years to reflect the internationality of the Olympic movement. As the first modern Olympic Games was held in Athens, Greece on 1896, Kailas VI of Greece was the first president. After the Athens Olympic Games, the next Olympic Games will be held in Paris, France at 1900, so Coubertin took over as the second president. The third Olympic Games will be held in St. Louis, USA on 1904. Therefore, after the Paris Olympic Games, Coubertin will hand over the presidency to Si Long, an American member of the International Olympic Committee and a professor at Princeton University. However, Si Long believes that frequent changes of leaders are very unfavorable to the newly born International Olympic Committee, and insists on paying homage and staying in office. History has proved that Si Long's opinion is correct. During his 29 years as president of the International Olympic Committee, Coubertin made a series of great contributions to the survival, development and innovation of the Olympic Movement. After Coubertin, Valle latour of Belgium (1925- 1942), Ed Strong of Sweden (1942- 1952) and brundage of the United States (1952-/).