The Primera A is the top league competition in Colombia and has been running since 1948. Like most South American leagues it has had a mixed up history with a number of different formats and set-ups gracing the league over the years. The current format was set up in 1999 and consists of a two part season (the opening half called the Apertura and the closing half known as the Finalizacion). Due to sponsorship commitments it is now called the Copa Mustang. Teams play each other once in each season and also clash with their local rivals an extra time. The eight best teams qualify for a knockout stage where a champion is eventually crowned after a two leg final. Once Caldas were the most recent winners of the competition when they triumphed in the 2009 Apertura. Three spots from the Copa Libertadores are available in the Copa Mustang and these are allotted to the winners of the Apertura and Finalizacion and also to the best non-champion team in these two competitions.

Since the competitions inception Millonarios and America de Cali have been the most successful sides in the country with 13 titles apiece. Other successful sides include Atletico Nacional and Deportivo Cali.