The Additional Member System (AMS) is a voting system in which there are constituency seats which are usually allocated on the First Past the Post basis and additional seats awarded using party lists in order to achieve a degree of proportionality. Sometimes there are conditions parties must fulfil win list seats.

For example in London a party must either have:

  • 5% or more of the total vote
  • 1 or more constituency seats

Alphabetical Index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z