The World Bridge Federation (WBF) is the international governing body of contract bridge. The WBF is responsible for world championship competitions, most of which are conducted at a few multi-event meets on a four-year cycle. The most prestigious championships are those for national teams in Open, Women, and Seniors categories: the Bermuda Bowl, Venice Cup, and Senior Bowl (jointly the biennial "World Teams Championships"), and the quadrennial World Team Olympiads, incorporated in the World Mind Sports Games beginning 2008.