Italy's banks are the latest trouble spot for the eurozone.
They are struggling with a burden of bad debt, loans that are unlikely ever to be repaid fully.
They are a potential flashpoint in an economy that has for some time been seen as posing wider risks to the EU's currency area.
Meanwhile, the Italian government is considering a banking sector bailout which could breach European Union rules.
It's the size of the Italian economy and its government debt that makes the country a smouldering financial volcano. The risks are aggravated by the political situation.
It's the third-largest economy in the eurozone. The government debt burden, depending on which figures you look at, is certainly one of the largest in the eurozone, indeed the largest by one measure.