The International Monetary Fund (IMF) is an international organization responsible for managing the global financial system and for providing loans to its member states to help alleviate balance of payments problems. Part of its mission is to help countries that experience serious economic difficulties. In return, the countries who are helped are obliged to launch certain "reforms," such as privatizations of government enterprises.
One criticism from economists has been that the so called "Conditionalities", including Structural Adjustment Programmes, on which the financial aid is always bound, retard social stability and hence inhibit the IMF's targets. By discouraging the development of infrastructure and demanding austerity, the IMF Conditionalities restrict the economies of Third World nations to simply providing cheap labor and cheap raw materials to the G-7 nations, which critics claim is a disguised form of colonialism.
Adherents of supply-side economics generally find themselves in open disagreement with the IMF because typically the IMF advocates a Keynesian approach to economics. It may advocate currency devaluation so as to export more goods (which supply-siders see as inflationary). This is recommended by the IMF to the governments of poor nations with struggling economies. Supply-side economists claim these Keynesian IMF policies are destructive to economic prosperity, although many other economists disagree.
That said, the IMF sometimes advocates "austerity programmes", increasing taxes even when the economy is weak, in order to generate government revenue and balance budget deficits, which is the opposite of Keynesian policy.
Opposition to the IMF can be very fragmented. For instance advocates of Supply-side economics would in general regard the policies advocated by ATTAC to be little different in form to the ideas peddled by the IMF. In other words, they would see ATTAC tax and spend policies and the IMFs austerity policies as being fundamentally similar.
Argentina, which had been considered by the IMF to be a model country, experienced a serious economic crisis in 2001. This crisis created a movement of popular hatred against this institution within Argentina, with many blaming the IMF for the country's economic problems.
"When a nation is down and out, the IMF takes advantage and squeezes the last pound of blood out of them. They turn up the heat until, finally, the whole cauldron blows up. It has condemned people to death." (1 p.50-51)