The binomial system is a voting system that was used in the parliamentary elections of Chile between 1989 and 2013. From a voting system point of view, it is a multiple-winner method of proportional representation with open lists, where winning candidates are chosen through the D'Hondt method. Its particularity comes from the fact that only two candidates are elected in each district, resulting in an over-representation of the second majority list. Its use was prescribed in the respective constitutional organic law during the Pinochet regime.