High Quality Content by WIKIPEDIA articles! The Additional Member System (AMS) is a branch of voting systems in which some representatives are elected from geographic constituencies and others are elected under proportional representation from a wider area, usually by party lists. Voters usually have two votes, one for the party and the second for the candidate in a constituency (sometimes these votes are combined). The constituency representatives are generally elected under the first-past-the-post voting system. The party representatives are elected by a party vote, where the electors vote for a political party, and usually not directly for an individual. The particular individuals selected come from lists drawn up by the political parties before the election, at a national or regional level.