The Primeira Liga, also known as Liga NOS for sponsorship reasons, is the top professional association football division of the Portuguese football league system. It is organised and supervised by the Liga Portuguesa de Futebol Profissional. As of the 2014–15 season, the Primeira Liga is contested by 18 teams, with the two lowest placed teams relegated to the Segunda Liga and replaced by the top-two non-reserve teams from this division (except in the 2018–19 season in which the three lowest placed teams are relegated to the Segunda Liga due to the integration in the Primeira Liga of Gil Vicente in the next season. However, the Portuguese Football Federation appealed to proceed with this integration as soon as possible.