Parliamentary Labour Party

In UK politics, the Parliamentary Labour Party (PLP) is the parliamentary party of the Labour Party in Parliament: Labour MPs as a collective body.

Commentators on the British Constitution sometimes draw a distinction between the Labour Party (which was created outside Parliament and later achieved office) and the Conservative and Liberal parties (which began as parliamentary factions). The term 'Parliamentary Labour Party' properly refers to the party in parliament, whereas the term Labour Party refers to the entire Labour Party, the parliamentary faction of which is the PLP.

Originally, the Leader of the Labour Party was elected by the PLP. Nowadays, an electoral college is used, consisting of three sections – MPs and MEPs, affiliated organizations (trade unions and socialist societies), and Constituency Labour Parties (CLPs). A person can be counted in multiple categories, so, for example, an MP who belongs to a trade union, one socialist society, and a CLP gives four votes (although the vote he gives for being an MP is by far the most influential one). The single transferable vote is used to conduct the election.

Labour MPs retain the power to trigger an extraordinary or "special" Labour Party Conference to choose a new leader if they lose confidence in their existing leader.

Labour MPs also elect two of their number to Labour's National Executive Committee.

The PLP holds regular meetings behind closed doors to question the Leader and to discuss its concerns.

A similar body for the Conservative Party is the 1922 Committee.