March Madness is a popular term for season-ending basketball tournaments played in March (Brent Musburger is generally regarded as the individual who first used that phrase in conjunction with the college tournament, using it during CBS Sports' coverage of the tourney back in 1982 - see below), especially those conducted by the National Collegiate Athletic Association (NCAA) and various state high school associations. The phrase was not associated with the college tournament in 1939, when an Illinois official wrote "A little March Madness [may] contribute to sanity." March Madness is also a registered trademark, held jointly by the NCAA and the Illinois High School Association. The trademark has sparked a pair of high-profile courtroom battles in recent years.

March Madness refers to the frenzy these tournaments ignite among sports fans and, at least at the college level, sports gamblers. As it applies to college basketball, the term originally referred to the conference basketball tournaments, which occur in March just before the NCAA tournament begins, but in recent years has been used to refer to the NCAA tournament itself (the first weekend of which involves some 49 games, and which actually runs into early April). The term is now used in reference to both the men's and women's tournaments. The Big Dance also refers exclusively to the NCAA Tournaments to distinguish them from the conference tournaments and the NIT.

As a tournament ritual, the winning team cuts down the net at the end of the regional championship game (and the national championship game). Each player cuts a single strand off of the net for themselves, commemorating their victory, with the head coach cutting the last strand and claiming the net itself. Furthermore, the regional champs (starting in 2007) receive a bronze plated NCAA Regional Championship trophy (previously given to only the Final Four teams that did not make the championship game), and the National Champions also receive a gold plated NCAA National Championship trophy along with a more elaborate marble/crystal trophy sponsored by Siemens. The loser of the championship game receives a silver plated National Runner-Up trophy for second place.