Former US President Mr Bill Clinton today urged the people of Northern Ireland to continue on the road to peace and lead the world by their example.
Mr Clinton said he understood the process was difficult, but he asked the people of Northern Ireland to "vote for peace".
The former president also urged politicians to fully implement the Belfast Agreement during a speech in Derry to mark Mr John Hume's appointment to the Tip O'Neill Chair of Peace Studies at the University of Ulster.
"I ask you to stay the course and lead the world by your example," he said.
"When the Middle East peace fell apart, when the future was uncertain in Bosnia, when Africa was still reeling from losing 10 per cent of the people in the entire country of Rwanda and 2 million died in the Congo, I could always point to the Good Friday Accord.
"You need to think a long time before you give it up." Mr Clinton told a room of invited guests, including Sinn Féin leader Mr Gerry Adams, the party's chief negotiator Mr Martin McGuinness and SDLP leader Mr Mark Durkan, he understood the full implementation of the Good Friday Agreement was difficult.
However, he asked whether the situation in Northern Ireland was any worse than in other troubled areas of the world.
"In a world that is coming together, I think the Good Friday Accord is about the best you could ever do - the principle of consent," he said.
"The majority rule, the minority rise, shared political responsibilities, shared economic benefits, special relationships with both the UK and the Irish Republic.
"The assumption that if everyone is treated fairly now when one religious or political group is in the majority, that 30 years from now, if present birth rates continue and emigration doesn't render it totally irrelevant, the other will be in a majority, it will work out fine then too when we're all integrated into much bigger units anyway.
"I don't think you can do much better than that and I think that's why the deal was made in the first place."
Mr Clinton said all of human history had basically been a race between the ability "to see the common humanity of people who are different from us and our increasing ability to kill them with technological advances."
"I have studied every peace agreement made and everyone not made everywhere in the world in the last 50 years, nobody could have done a better job in reconciling the complicating and conflicting interests than you did in this agreement," he said.
"It's about as local as you can get and still sees the possibilities of the modern world.
"I know implementing it is tough, all I can do is ask you to remember all the other hard places in the world and how much better it is that we're sitting here today talking to each other and not worrying about a bomb going off.
"And so I'm asking, just like Tip O'Neill would, I want your vote for peace." Mr Clinton's address to the Great Hall at the university's Magee campus marked his third trip to Derry.
He first visited the city in November 1995, while he was US President. He also stopped off there in May 2001.
PA