FIDE World Chess Federation

FIDE's most visible activity is organizing the World Chess Championship (overall and for women and juniors), regional championships and the Chess Olympiad. It is recognized by the International Olympic Committee (IOC) as the supreme body responsible for the organization of chess and its championships at global and continental levels.^[3] FIDE oversees few other tournaments, although other top-level events, almost without exception, respect FIDE rules and regulations.

It defines the rules of chess, both for playing individual games (i.e. the board and moves) and for the conduct of international competitions. The international competition rules are the basis for local competitions, although local bodies are allowed to modify these rules to a certain extent. FIDE awards a number of organisational titles including International Arbiter, which signifies that the recipient is competent and trusted to oversee top-class competitions.^[4]

FIDE calculates the Elo ratings of players and uses these as the basis on which it awards titles for achievement in competitive play: FIDE Master, International Master, International Grandmaster, and womens versions of those titles.^[5] It also awards Master and Grandmaster titles for achievement in problem and study composing and solving, and periodically publishes FIDE Albums of the best problems.^[6]

Correspondence chess (chess played by mail) is regulated by the International Correspondence Chess Federation, an independent body that co-operates with FIDE where appropriate.