Announcing the decision, the Nobel committee said MSF, known in English as Doctors Without Borders, deserved the last prize of this violent century for its "pioneering work" in the world's troublespots - and its insistence that it had a right and duty to alleviate suffering, whether caused by natural disasters, conflict or political oppression.
"There were 136 candidates this year, and we deemed Doctors Without Borders as the most worthy," the awards committee chairman Francis Sejersted said in Oslo. "This was first and foremost a recognition of what they have done over many years."
MSF won almost £585,000 and dashed the hopes of Chinese dissidents and Middle East peacemakers for the annual honour, which was bequeathed by Alfred Nobel, the inventor of dynamite.
Set up in 1971 by French doctors disgusted at the studied neutrality of the Red Cross during the horrors of the Biafran war, MSF overcame early scepticism - and epithets such as "medical hippies" - to become a trendsetter for groups combining relief work with human rights advocacy.
MSF is highly proactive, with a policy of témoinage, or witnessing, that includes establishing a presence near people in danger and engaging in condemnation when there are violations of human rights and international law.
Founder members included Bernard Kouchner, the former French health minister and now the head of the UN mission in Kosovo. "I'm very emotional and very aware of the political importance of this prize," he said yesterday. "There have been detractors, people who laughed at us, but that's normal. They didn't understand."
Today the Brussels-based organisation has 23 offices around the world and sends about 2,500 volunteers - 150 of whom are from Britain and Ireland - to some 80 countries each year. With an annual budget of £150m, it played a key role in the crises in Kosovo and East Timor, where its doctors were the last medical workers to leave at the height of the fighting and among the first to return.
About 70% of the volunteers are medically trained. The charity also employs engineers, sanitation experts and administrators. The average contract is nine months, but surgeons often offer their expertise for three or four weeks. Volunteers receive a subsistence allowance of about £400 a month.
MSF is now a permanent feature of the international nongovernmental effort. In the messy geopolitics of the post-cold war era, where most conflicts are now within rather than between states and most victims are civilians, the media-savvy MSF has found no shortage of work.
"It is very good news - congratulations to MSF," enthused Kris Janowski, spokesman for the UN high commissioner for refugees. "Their staff members are all wonderful people, very devoted to their work. We've seen them in the darkest corners of the earth trying to help people in need of help."
Other groups applauded the prize. "This says that the role of NGOs and humanitarian organisations is becoming increasingly important," said Simon Bottery of the British development group ActionAid. "Depressingly it also means that their work is becoming increasingly necessary. MSF are very highly regarded and they are seen as very professional."
Aid workers want the recognition for MSF to highlight the difficulties of dealing with the victims of complex emergencies and the need to develop internationally accepted standards of performance and accountability.
It comes as agencies worry that their efforts are being used as a substitute for political and diplomatic action to prevent and end conflicts. In Rwanda in 1994, MSF doctors from Holland withdrew after realising they were unwittingly giving help to killers in the refugee camps.
MSF has always fiercely guarded its independence. Phillipe Biberson, president of MSF France, greeted news of the prize with apprehension as well as pride "It might, in fact, complicate our work," he warned. "It's not clear that the institutionalisation of humanitarian aid is the best way to defend endangered populations."
Another aid expert said: "Its a big tribute to MSF but it may be invidious to single out a single organisation... There are a lot of other humanitarian workers out there, too, working through thick and thin and with a much lower profile."
Four organisations have won or shared the peace prize in the past 20 years, but this was the first humanitarian field organisation to win since the UNHCR in 1981. The first prize, in 1901, was shared by the Red Cross founder Jean Henri Dunant.
MSF was chosen over the Israeli president Ezer Weizman, the Chinese human rights activist Wei Jinsheng, the Salvation Army and the Colombian Children's Peace Movement.
Nobel causes
Nobel peace prize winners of the 1990s
1999 : Médecins sans Frontières
1998 : David Trimble and John Hume
1997 : Jody Williams and the International Campaign to Ban Landmines
1996 : Bishop Carlos Belo and Jose Ramos-Horta of East Timor
1995 : Joseph Rotblat, Pugwash Conference on Science and World Affairs
1994 : Yasser Arafat, Yitzhak Rabin and Shimon Peres
1993 : Nelson Mandela and FW de Klerk
1992 : Rigoberta Menchu, Guatemala
1991 : Aung San Suu Kyi, Burma
1990 : Mikhail Gorbachev, Soviet Union
