Q&A: Greek debt crisisContinue reading the main story
The European Commission, the European Central Bank (ECB) and the International Monetary Fund (IMF) are due to return to Athens this week to review Greece's debt reduction programme.
At stake is the next tranche of bailout money the government needs to pay its bills.
This is money from the 110bn euro ($148bn; £95bn) bailout agreed last summer. Eurozone leaders have subsequently agreed a further 109bn euro package, but this has yet to be fully ratified by member states.
The wider aim of the bailouts is to shore up Greece's economy, calm the financial markets, and stop contagion spreading to other debt-laden European economies.
However, despite denials from some leading member countries, particularly Germany, there is a growing feeling in the markets that Greece will default on its debts. In fact many observers see it as inevitable.
Why is Greece in trouble?
Greece has been living beyond its means in recent years, and its rising level of debt has placed a huge strain on the country's economy.
The Greek government borrowed heavily and went on something of a spending spree after it adopted the euro.
Public spending soared and public sector wages practically doubled in the past decade.
However, as the money flowed out of the government's coffers, tax income was hit because of widespread tax evasion.
When the global financial downturn hit, Greece was ill-prepared to cope.
It was given 110bn euros of bailout loans to help it get through the crisis - but has now needed another 109bn euros.
Why did Greece need another bail out?
Greece received its original bailout in May 2010.
The reason it had to be bailed out was that it had become too expensive for it to borrow money commercially.
It had debts that needed to be paid and as it couldn't afford to borrow money from financial markets to pay them, it turned to the European Union and the International Monetary Fund.
The idea was to give Greece time to sort out its economy so that the cost for it to borrow money commercially would come down.
But that did not happen. Indeed, the ratings agency S&P recently decided that Greece was the least credit-worthy country it monitors.
As a result, Greece has lots of debts that need to be paid, but it cannot afford to borrow commercially and does not have enough money from the first bailout to pay them.
Despite the bailouts, many people think Greece will default.
They certainly do in the financial markets, which seem to have accepted that Greece is heading for an "orderly default".
In July, eurozone leaders proposed a plan that would see private lenders to Greece writing off about 20% of the money they originally lent, whereas the latest plan is expected to include a 50% write-off.
What continues to worry the markets, however, is fear of a "disorderly default" and the domino effect that might have within the eurozone.
Major eurozone governments have been criticised for a lack of political leadership, and there have been signs of divisions within the ECB.
The concern in the markets is that the eurozone's political structures do not have the authority to deal with the magnitude of the economic problems.
Could the crisis spread?
The aim of the last Greece bailout - as with the first bailout - is to contain the crisis.
The bailouts of Portugal and the Irish Republic were designed to tide both countries over until they could borrow commercially again, just as was hoped for Greece.
If that hasn't been possible in Greece, investors may question whether the same solution will work for the other two bail-out recipients.
There are also concerns about the situations in Italy and Spain, both of which have seen their borrowing costs rise.
The Spanish and Italian economies are far bigger than those of Greece, Portugal and the Irish Republic and the European Union would struggle to bail them out if that became necessary.
What would happen if Greece defaulted?
Europe's banks are big holders of Greek debt, with perhaps $50bn-$60bn outstanding. An "orderly" default could mean a substantial part of this debt being rescheduled so that repayments are pushed back decades. A "disorderly" default could mean much of this debt not being repaid - ever.
Either way, it would be extremely painful for banks and bondholders.
What's more, Greek banks are exposed to the sovereign debts of their country. They would need new capital, and it is likely some would need nationalising. A crisis of confidence could spark a run on the banks as people withdrew their money, making the problem worse.
That confidence crisis may spread to overseas banks, which could stop lending until the full extent of a default was known. It might be a repeat of the credit crunch that pushed European and the US into recession three years ago.
What would it mean for the eurozone?
A Greek exit is seen by some as inevitable if the country defaulted. The big question would then be, what about other heavily-indebted nations?
If Greece can force a "haircut" on its creditors, then why not Portugal or the Republic of Ireland?
The political and economic structures that have bound the 17-nation bloc together could begin to unravel.
German public opinion is already tiring of the government's lead role in bailing out the eurozone in a bid to hold the bloc together.