The Commons speaker, Michael Martin, has announced he is stepping down on 21 June. His successor will be chosen by MPs the following day. Here are some of the names being talked about in connection with the job.
SIR ALAN BEITH - LIKELY TO STAND
Veteran Lib Dem MP, with more than 30 years' experience. Former party leadership contender. Chairman of the constitutional affairs committee. Respected figure who was in the running for the job in 2000. He told the BBC News channel he would stand if he could gain sufficient cross-party support, adding: "I have started to get indications of that from people in at least three parties". He added: "It's something I care deeply about - making the House of Commons once again acceptable to the people of this country as the core of our democracy. He said the job of Speaker should be to "lead on reform" rather than defend the status quo and to strengthen MPs ability to challenge the government. But asked if the new Speaker had to be "whiter than white", he joked: "Nobody is whiter than white." He said he had once claimed twice for the same television licence but immediately sent off a cheque when he realised his mistake.
SIR GEORGE YOUNG - YET TO CONFIRM
Conservative grandee and widely-respected chairman of the Standards and Privileges Committee. One of the bookmakers' favourites to land the job of Speaker after missing out in 2000. But Eton-educated background may count against him in the eyes of Labour MPs. Ladbrokes make him 8/1.
SIR ALAN HASELHURST - YET TO CONFIRM
Conservative MP and deputy speaker. Widely-respected figure who also served as deputy to former Speaker Betty Boothroyd. Another favourite at the bookmakers but being singled out by The Daily Telegraph for claiming £142,119 in second homes allowances since 2001, despite having no mortgage on the property, will not help his chances. Joint favourite at 4/1 with Frank Field, according to Ladbrokes.
SIR MENZIES CAMPBELL - YET TO CONFIRM
Former Liberal Democrat leader. Respected for his integrity on all sides of the house and was one of the favourites to land the job last time. But chances may be hampered by criticism of his second home allowance claim.
FRANK FIELD - YET TO CONFIRM
Maverick former Labour minister who sometimes seem more respected on Opposition side of the house - which may count against him if he decides to run. Led successful campaign to reverse 10p tax band cut. Has also led calls for wholesale reform of the Commons.
JOHN BERCOW - YET TO CONFIRM
Backbench Tory MP. Former right winger, who has moved towards the centre in recent years. Thought to have the backing of several Labour MPs for the Speaker's job but may not be popular enough with his own side to stand a realistic chance. Ladbrokes have him at 8/1.
SIR PATRICK CORMACK -YET TO CONFIRM
Veteran Tory backbencher who was in the running for the job last time. Chairman of the Northern Ireland Affairs Committee. Expert on constitutional affairs but may be seen as too much of a traditionalist to lead changes demanded by most MPs.
CHRIS MULLIN - YET TO CONFIRM
Former Labour minister and diarist, with an independent-minded streak. Standing down at the next election but has been talked of as a possible interim candidate for Speaker, who might gain the necessary cross-party support.
TONY WRIGHT - YET TO CONFIRM
Widely-respected chairman of the public administration committee, who has led a number of investigations into the conduct of MPs and civil servants. Has been talked of by some as a possible contender from the Labour benches.
SYLVIA HEAL - YET TO CONFIRM
Labour MP and deputy speaker. Sister of Labour MP Ann Keen, who organised Michael Martin's successful campaign for the Speakership in 2000.
RICHARD SHEPHERD - YET TO CONFIRM
Independent-minded veteran Tory MP, first elected in 1979. Has led criticism of Speaker Martin. Stood unsuccessfully for the Speakership in October 2000. Ladbrokes makes him 14/1.
Lib Dem Treasury spokesman Vince Cable, an early favourite with the bookmakers, has ruled himself out of the running for the Speaker's job. Another familiar figure, Ann Widdecombe, the former shadow home secretary, has also rejected calls from allies on the Tory benches to stand as an interim candidate until she stands down at the next general election. Former shadow home secretary David Davis has also ruled himself out.