Parliamentary vote is the method of voting used by deliberative assemblies. It consists of rules and procedures which, when combined, ensure decorum, allow full and free debate, and ascertain the will of the majority. A parliamentary vote may be a show of hands, a roll call, or a secret ballot. In a show of hands, members raise their hands or stand to indicate their preference. In a roll call, each member is called by name to cast his or her vote. A secret ballot is a method of counting votes in which the identities of voters are concealed. It is used in elections where the privacy of votes is important, as in a referendum.
The parliamentary system originated in the British Houses of Parliament and is still practiced in countries that were formerly part of the United Kingdom or were strongly influenced by the British political tradition. A parliamentary system may be bicameral, with two chambers (or houses) of parliament, or unicameral, with one parliamentary chamber. Some parliamentary systems use proportional representation, while others employ a first past the post electoral system and other methods for allocating seats in parliament.
Advocates of the parliamentary system contend that it is more responsive to public influence than the presidential system, because a governing party that loses popular support can be voted out of office at any time between periodic parliamentary elections. This can eliminate periods of legislative gridlock that can occur in a presidential system. In some parliamentary democracies, a prime minister and cabinet of executive ministers can be replaced even during the middle of their term. Some parliamentary systems also require that anti-defection laws be enforced to prevent legislators from changing parties during their term, as is the case in Australia and New Zealand.