John Cain Arena is a multi-purpose sports and entertainment arena located within Melbourne Park in Melbourne, Victoria, Australia. It is the second-largest venue and show court for the Australian Open, the first Grand Slam professional tennis tournament held each calendar year. The arena also hosts various other sporting and entertainment events throughout the year.

The arena has sometimes been dubbed "The People's Court" during Australian Open matches, owing to its accessibility for Australian Open patrons with a ground pass (i.e. the cheapest form of ticketing available) and the close proximity of spectators to the players, with the arena developing a reputation for being an incredibly passionate venue with a terrific atmosphere, particularly when Australians are playing on the court.