Mr Hume (left) was succeeded by Mark Durkan as leader
John Hume has dedicated his political career to helping build a climate in which parties on both sides of the political divide could work together.
The 67-year-old former leader of Northern Ireland's Social Democratic and Labour Party (SDLP) was jointly awarded the Nobel Peace Prize for his reconciliation work with Ulster Unionist leader David Trimble in 1998.
Respected and admired on both sides of the sectarian divide, Mr Hume has staked his whole professional credibility on the peace process.
When Mr Hume resigned his assembly seat in 2001, he said it would allow him to concentrate on his parliamentary duties at Westminster and his duties as an MEP.
Ill health was also a major factor in that decision.
A former teacher, Mr Hume first came to prominence through the civil rights movement in the late 1960s, when Catholics demanded substantial changes to the way Northern Ireland was run.
He helped to found the moderate nationalist SDLP in 1970, later taking over as its leader in 1979.
It was a role that won him influence in Dublin, London, Brussels and Washington.
Mr Hume campaigned for the SDLP in the last assembly poll
He was one of the driving figures behind many of the significant attempts to resolve the Northern Ireland problem over the last 35 years.
Like the Democratic Unionist Party leader Ian Paisley, he is one of the most enduring figures on the Northern Ireland political stage.
Mr Hume was a member of the power-sharing executive set up after the Sunningdale Agreement in December 1973.
He helped to shape the Anglo-Irish Agreement of 1985, which for the first time gave Dublin a limited say in the affairs of Northern Ireland.
Opened talks with republicans
In 1988, Mr Hume began a series of contacts with the Sinn Fein leader Gerry Adams, which were to prove crucial in developing the current process.
Further talks became public in 1993 amid considerable controversy and hostility, especially from unionists. In defiant mood, Mr Hume declared he did not care "two balls of roasted snow" about all the criticism he faced.
Mr Hume drew unionist criticism after talks with Gerry Adams
The former SDLP leader's strategy was to try to persuade Sinn Fein that the problem in Ireland was not so much the British presence but the divisions between the people of Ireland, unionist and nationalist.
Around the same time, contact between the UK and Irish Governments led to the Downing Street Declaration, followed by the first IRA ceasefire in 1994.
Mr Hume strongly supported the view that any talks about the future of Northern Ireland should be as inclusive as possible, and when the Good Friday Agreement was signed in 1998, the participants included Sinn Fein as well as political representatives of Protestant paramilitaries.
He went on to campaign vigorously for a Yes vote in the referendum on the Agreement, symbolically shaking hands with his co-Nobel prize winner, Ulster Unionist leader David Trimble, in an effort to swing the unionist vote.
Resigned as leader
Mr Hume topped the poll in the Foyle constituency in the 1998 assembly election with 12,581 votes.
The SDLP leader also comfortably topped the poll in the 1997 general election in the constituency with 25,109 votes.
He has been Foyle's MP since the constituency was created in 1983 and a member of the European Parliament since 1979.
But his huge workload has taken a toll on his health, and Mr Hume stood aside to let fellow SDLP member Seamus Mallon assume the Deputy First Minister role in the new Northern Ireland Assembly.
In August 1999, Mr Hume was rushed to hospital while attending a conference in the Austrian resort of Alpbach.
He resigned as leader of the SDLP in September 2001, having been at the helm for 22 years.
He said he had suffered from serious health problems and would be cutting down on his workload.
The Foyle MP was succeeded by Mark Durkan as leader of the SDLP.