Open list describes any variant of party-list proportional representation where voters have at least some influence on the order in which a party's candidates are elected. This as opposed to closed list, which allows each party to determine the order of its candidates and gives the voter no influence at all within a party.

There are still differences possible between open list systems, each giving the voter varying amounts of influence:

1. A 'relatively closed' open list system would be one where a candidate has to get a full quota (usually Hare quota, but Droop quota is also possible) on his or her own in order to be elected. The total number of seats won by the party minus the number of its candidates that succeeded in getting this quota would then successively be given to those unelected candidates from that party who had been ranked highest on the original list.
2. For a 'more open' list system, the quota could be lowered to less than a full one instead (the Netherlands for example uses 25% for its Lower House elections). It is then (theoretically) possible that more candidates are eligible for a seat than the party deserves as a whole. It should therefore be clear in advance whether list ranking or absolute votes takes precedence in that case.
3. The 'most open' list system is the one where the absolute amount of votes every candidate got fully determines the "order of election" (the list ranking only possibly serving as a 'tiebreaker'). When such a system is used, one could make the case that 'within' every party an additional virtual single non-transferable vote election is taking place. This system is used in all Finnish multiple-seat elections, with ties being resolved by a toss.

Additionally, an open list system could also allow a voter to vote for the party as a whole without expressing a preference between individuals. In practice however, voting for the most popular candidate or (except in the 'most open' system) the first candidate on the list will give the same effect.

See also

• List of democracy and elections-related topics

The difference between "Open" and "Closed" lists has been debated in B.C., Canada, during the Learning Phase of Week 5, 2004 http://www.citizensassembly.bc.ca/public/learning_resources/learning_materials/week5