Protesters say the WTO is a club for the rich
Money makes the world go round, so the World Trade Organisation meeting in Cancun, Mexico matters to us all.
International trade is worth $11bn a day - for most of us in developed countries it means wealth scarcely dreamt of.
But there is no such thing as a free lunch and probably no free trade without a price either.
Campaigners for a less unequal world fear the poor will pay Cancun's price.
The argument is fairly simple when you remember that the planet's poorest 50 countries, with about 10% of the Earth's population, account together for less than 0.5% of world trade.
So Cancun can do very little for them unless it can offer them a massive increase in their share.
Some countries have precious little to sell on the international market anyway.
If they decide self-sufficiency is the only way forward, the WTO is at best irrelevant.
The experience of many countries which have tried to sell their produce around the world is discouraging.
If your main export is coffee, for instance, or copper, or bananas - whose prices have fallen drastically - you may feel the bottom has dropped out of your world and more liberalised trade is the last thing you need.
The developed countries make the rules, and - perhaps not surprisingly - they drive a hard bargain.
That is one of the campaigners' chief objections to the WTO, that it is a club to make the rich richer.
Its former director general, Mike Moore, said in 2000: "There is no denying that some members are more equal than others."
Some campaign groups also complain of "blackmail, arm-twisting and bullying" behind the scenes at the WTO.
One of the toughest issues in Cancun will be agriculture.
The environmental pressure group Friends of the Earth believes the plans for agricultural trade agreements are a direct threat to the environment.
The subject of agriculture is particularly contentious in Mexico
"The large-scale, export-oriented agriculture that is promoted in current WTO proposals is... the main cause of deforestation, especially in tropical areas," Simone Lovera of Friends of the Earth says.
"It is now widely recognised that the recent increase of deforestation of the Brazilian Amazon is mainly caused by the rapid expansion of soy bean production for the mainly European export market."
So the wealth of living creatures in the forests will be hustled more rapidly towards extinction, Friends of the Earth believes, all to swell the burger barons' profits.
Agriculture is an example of another of Cancun's contentious problems: the subsidies rich countries pay their own producers - enabling them to swamp the poor world with cheap products - and the tariffs they impose to deter exports from the their poorer competitors.
Without real progress on both subsidies and tariffs in Mexico, there are going to be some bitterly disappointed and frustrated people.
Not many observers are holding their breath, though.
Beyond that lies the question of which international agreements matter more, trade or environment treaties.
Friends of the Earth says clean air and marine turtles have already fallen victim to the presumption that the WTO's rules will always take precedence.
It fears the forests may be the next to suffer.
So, without some pretty unexpected results from Cancun, the wretched of planet Earth look likely to be little better off after the captains and the kings have returned to Washington, London and Geneva.
That really would matter to us all. One lesson of the last two years is that poverty and frustration can, sooner or later, boil over in horrific ways.
And beyond that, the poor lack the choices of the rich.
They cannot choose to think about tomorrow, or the next generation, if they are to survive tonight.
And what they destroy to survive is what we all depend on in the end.