The question is whether Greece's problems will spread to other indebted eurozone countries, and what that means for the euro itself.
Germany, the richest of the euro-one nations, has problems of its own - its economy is not growing.
It is also reluctant to offer Greece financial help, because German voters face unemployment and a bad economic environment. They see no reason why they should give money to Greece, which everyone agrees has been spending more money than it should and cooking the books so nobody knew.
All the same, some experts say if nothing is done for Greece, there may be a knock-on effect that will cause a lack of confidence in the euro. If the euro significantly devalues, it will be good for manufacturing nations like Germany, whose products will become cheaper.
But it could affect the fragile US economy whose exports will become more expensive in Europe.
'The major implications are for Greece, Spain, Portugal, Italy and Ireland, and therefore in some sense for all of Europe,' Joseph Stiglitz, a Nobel Prize-winning economist at Columbia University, said.
