The Campeonato Brasileiro Série A, commonly known as the Brasileirão, is Brazil's top-tier professional football league and one of the strongest and most-watched competitions in the world. Its history is unique due to Brazil's vast size and early reliance on state championships, with nationwide tournaments like the 1959 Taça Brasil and the 1967 Torneio Roberto Gomes Pedrosa eventually being declared official Brazilian titles (along with the retroactively recognized 1937 Torneio dos Campeões). After years of highly variable formats that once included 92 clubs in 1979, the league has settled since 2006 into a consistent double round-robin system featuring 20 clubs and 38 matches per season. Globally dominant, it was ranked the strongest national league by the IFFHS in 2021, is the most-watched league in the Americas (broadcast to 155 nations), and is valued at over $1.43 billion. Brazilian teams have also achieved remarkable international success, claiming the second-most Club World Championship titles (10) and tying Argentina's top flight for the most Copa Libertadores wins (25).