Summer Olympic Games demand for tickets to all levels of each event, there was controversy when seats set aside for sponsors and National Delegations went unused in the early days. A system of reallocation was put in place so the empty seats were filled throughout the Games. Rio de Janeiro, Brazil hosted the 2016 Summer Olympics, becoming the third city in the Southern Hemisphere to host the Olympic Games after Melbourne, Australia, in 1956 and Sydney, Australia, in 2000, and the first South American city to host the Olympics. The preparation for these Games was overshadowed by controversies, including the instability of Brazil's
Independent Olympians at the Olympic Games their only competitor in athletics at the 2016 Olympics. On December 5, 2017, the IOC announced that Russia would be banned from the 2018 Winter Olympics over its state-sponsored doping program. Russian athletes were allowed to participate under the Olympic flag as "Olympic Athletes from Russia" (OAR) if they were cleared by a panel, which was chaired by Valerie Fourneyron and had representatives from the IOC, the World Anti-Doping Agency, and the Doping Free Sport Unit of the Global Association of International Sports Federations. Independent Olympians at the Olympic Games Athletes have competed as Independent Olympians at the Olympic Games