In the House of Lords a panel of 20 to 25 Deputy Speakers assist the Lord Speaker in presiding over debates when the Lord Speaker is not present. Unlike the Lord Speaker, Deputy Speakers may continue to participate in debates and vote in divisions, even when they are sitting on the Woolsack. Deputy Speakers are appointed by the Crown. By practice, all Deputy Speakers will also be Deputy Chairmen. The difference is that the latter are appointed by the House at the start of each session, whereas Royal Commissions occur only occasionally. Deputy Chairmen and Deputy Speakers exercise the same functions in the House. Of the panel of 20 to 25, the Chief Whip and Opposition Chief Whip are also Deputy Speakers and sit on the Woolsack if no other Deputy is present. The first of the Deputy Speakers is ex officio the Chairman of Committees. The panel also includes the Chairman of the Lords European Union Committee (who is also the Principal Deputy Chairman of Committees), but whose duties with the EU Committee leave no time for sitting on the Woolsack.
In the House of Commons there are three Deputy Speakers. The Deputy Speakers are officially known as the Chairman of Ways and Means, the First Deputy Chairman of Ways and Means and the Second Deputy Chairman of Ways and Means.
Along with supporting the Speaker in the Chamber, the Deputy Speaker’s other responsibilities include overseeing the arrangements for sittings in Westminster Hall, and presiding over the House of Commons when it is in a committee of the whole House.