Stadium Australia is a multi-purpose stadium located in Sydney Olympic Park, a suburb of Sydney, New South Wales, Australia. The stadium, which is sometimes referred to as Sydney Olympic Stadium, Homebush Stadium or simply the Olympic Stadium, was completed in March 1999 at a cost of A$690 million to host the 2000 Summer Olympics. The Stadium was leased by a private company, the Stadium Australia Group, until the Stadium was sold back to the NSW Government on 1 June 2016 after NSW Premier Michael Baird announced the Stadium was to be redeveloped as a world-class rectangular stadium. The Stadium is owned by Venues NSW on behalf of the NSW Government.

A multi-purpose stadium is a type of stadium designed to be easily used for multiple types of events. While any stadium could potentially host more than one type of sport or event, this concept usually refers to a specific design philosophy that stresses multifunctionality over specificity. It is used most commonly in Canada and the United States, where the two most popular outdoor team sports—Canadian football or American football and baseball—require radically different facilities. Football uses a rectangular field, while baseball is played on a diamond with a large outfield. Since Canadian football fields are larger than American ones, the design specifications for Canadian facilities are somewhat less demanding. The particular design to accommodate both is usually an oval, although some later designs use an octorad. While building stadiums in this way means that sports teams and governments can share costs, it also presents some challenges.