The banking industry has described its agreement with Greece to cut its debts as "unprecedented".
A group of banks and other investors in Greek government debt have agreed to exchange their debt for new bonds that are worth much less and pay a modest rate of interest.
Including the reduced interest rate, the losses to the banking industry are more than 70%.
For some of Europe's biggest banks, that means heavy losses.
"The losses are going to be substantial, but they are contained and there's a longer-term benefit for the system in having a core group of investors sit down across the table and coming together," said Charles Dallara, managing director of the Institute for International Finance, which negotiated on behalf of the banking industry. Continue reading the main story �Start Quote
In the long and tawdry history of governments borrowing more than they can afford, this represents a remarkably huge, unprecedented write-off�
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It is perhaps no great surprise that Greek banks are the most exposed to Greek debt.
According to Barclays Capital, the top two holders of Greek debt are National Bank of Greece, with 13.2bn euros ($17.5bn), and Eurobank EFG, which holds 7.3bn euros ($9.7bn).
Once the bond exchange is completed, those holdings will be worth less than half their current value, and if you include future interest payments, worth 70% less.
Outside Greece, French and German banks hold the most Greek debt. The last bailout?
Many foreign banks have already accepted that their investments in Greece are now worth just a fraction of their original value, irrespective of the latest deal.
In its most recent set of results, France's BNP Paribas, the biggest owner of Greek debt outside Greece, said that it had written down the value of its Greek debt by 75% on its balance sheet.
And according to the Barclays report, Commerzbank is the biggest holder of Greek debt among Germany's banks. Its holdings of government debt have complicated its efforts to raise new finance to boost its balance sheet.
For the average investors, the effect of Tuesday's bailout is limited. Most insurance companies and investment firms have little or no exposure to Greece.
Some hedge funds have built up their holdings in Greek debt, but it is likely to be a relatively small amount, perhaps less than five billion euros.
It is thought some will refuse to sign up to the bailout deal and hope to be repaid in full.
Analysts are now wondering whether the latest deal will be enough. The Greek economy is in recession, making it even more difficult for the nation to pay its debts.
"The debt sustainability analysis is much worse than people were expecting," said Laurent Fransolet, head of fixed-income strategy research at Barclays Capital.
"It's ambitious and we cannot be sure this is the last bailout. Does it buy a bit more time? Yes. But the next one will have to involve the official sector much more."