The IMF is the world's lender of last resort, where governments go when they cannot pay their debts. At one time or another most countries have been there - Britain knocked on the door of its smart Washington headquarters in the Seventies. As bank manager to national governments, it has never been exactly popular. It has frequently been accused of causing poverty in the Third World with its tough structural adjustment programmes, the financial equivalent of cod liver oil.
Now it is coming under heavy fire in the US - from left and right, but also from mainstream establishment figures such as the former secretary of state, George Shultz, who has argued for its abolition. Though the fund and its supporters in the US administration are toughing it out, the assault has them worried.
The IMF, having put together huge Asian and Mexican rescue packages, needs more money, and is passing round the hat to all of its shareholders: national governments. But a request to the US for an extra $18bn (pounds 11.25bn) has stalled in Congress, where the Republican leadership is refusing to sign the cheque. The right wants the fund to make countries it lends to agree to restrict abortion, among other conditions. Left-wing Democrats, for their part, contend that the IMF causes more problems than it solves, lacks democratic accountability and penalises the poor.
Though they recognise that its role has become far more complicated as global capital flows have exploded, and see its flaws, most mainstream analysts think the idea of abolishing the IMF is fanciful. But there will be changes in the way it operates, and its managing director, Michel Camdessus, knows this. The fund has started to open itself up more to scrutiny, for a start.
But the most important shift may be a recognition that the explosion in global capital flows over the past 10 years has altered the balance of power between governments and markets. In part this reflects the fact that the Asian crisis was different from previous episodes. It was caused by an eruption of bad debt in the private sector, rather than - as in the Latin American crises in the Eighties - governments that were terrifyingly over-extended.
The IMF has recognised that in future it will have to work more closely with creditor banks at the start of crises rather than dealing mainly through central banks and governments. This would help to defuse one criticism from the free-market right, by bringing in the private sector.
But adapting to the new world of global finance will also mean tougher treatment of the banks. One of the biggest criticisms of the IMF - one that even some of its supporters accept - is that much of the cash that it doles out to countries in economic trouble goes straight back to rich bankers in New York, London and Tokyo. The left sees this as immoral; the free-market right is concerned that it risks "moral hazard", which in banking jargon means encouraging bankers to make poor decisions, safe in the knowledge that they will still get their money back.
"There is an overwhelming consensus in Congress that while the IMF may responsibly act to stabilise economies, it is not the IMF's role to bail out banks," says Congressman James Leach, who sponsored the Bill to boost the fund's cash.
In a recent speech, Mr Camdessus talked about the need to "catalyse private-sector financing so as to achieve more equitable burden sharing" - in plain English, to get bankers to take more responsibility for their decisions. Bailing out the banks is out of fashion; instead, "bailing in the private sector" is the new buzz phrase. If the banks want more power, then they also have to take more responsibility.
In their twin-track assault, the US left and right have underlined the lack of consensus on how to regulate casino capitalism in the new millennium. The IMF has been caught in the crossfire between nationalists, liberals, free-market capitalists and isolationists, each with a different solution. Some want it to do more; some want it to do much less, or even disappear. At 53 years old, the IMF, like the UN or Nato, is finding it hard to keep its footing in the fast-moving world of the Nineties.
IMF Asian rescues
Thailand: August 1997, 2.9bn Special Drawing Rights ($3.9bn)
Indonesia: November 1997, 7.4bn SDRs ($9.9bn)
Korea: December 1997, 15.5bn SDRs ($20.8bn)
Total IMF stand-by arrangements approved: 27bn SDRs. Total IMF agreements approved: 44bn SDRsReuse content