The forum grew out of mass protests and street battles
Discussions are under way at the World Social Forum - a gathering of anti-globalisation groups in Porto Alegre, southern Brazil - to try to develop an alternative to the policies being discussed at the World Economic Forum in New York.
The 26,000 delegates - and many more observers from around the world - are to spend three days debating controls on international money markets, the scrapping of the World Trade Organisation, and new forms of participatory democracy.
It's the anti-globalisation movement's first big gathering since the 11 September attacks in the United States.
Delegates are also keen to voice their opposition to Washington's war on terror.
Fleshing out the theory
Packed like sardines into three separate auditoriums with video links between them, almost 10,000 delegates listened to the keynote address, 'A world without war is possible'.
They heard US linguist and radical Noam Chomsky explain why he believes that the kind of globalisation defended by the World Economic Forum in New York and the bombing of Afghanistan are linked by a common disregard for the majority of the world's population.
But despite the applause, his keynote address gave little idea of how this vast, disparate gathering will set about achieving what it has set as its main goal - to move the anti-globalisation movement beyond mere protest towards formulating concrete alternatives.
Everyone here - and that means many more than the 26,000 officially registered - seems convinced that, in the words of the conference slogan, another world is possible.
During the coming days, it'll be the job of literally hundreds of plenary sessions, seminars and workshops to flesh out what that other world might look like.
It won't be easy. The range of views represented stretches from the many shades of the Marxist left, through an array of single issue campaigns and non-governmental organisations, to such liberal stalwarts as United Nations human rights commissioner Mary Robinson, former Portuguese premier Mario Soares, and half a dozen ministers from Lionel's Jospin's government in France.
There will be many around the world waiting in hope or intrepidation to see what all these come up with.