Top of the list of accomplishments was expansion of IMF resources. The new SDR allocation was perhaps the most noteworthy and unexpected decision: those observers who have proposed such a step in the current international crisis, or in past international crises, have usually been dismissed as pipe-dreamers (John Williamson, Dani Rodrik, George Soros, Joe Stiglitz…). In addition, there seems to have been some forward movement on international regulation of the financial sector, as the Europeans wanted. Although President Obama acquitted himself well overall, the failure to achieve agreement for coordinated additional fiscal stimulus, as the Americans wanted, was probably the greatest shortcoming of the meeting.
I believe the G-20 meeting will be remembered historically, but not primarily for the above reasons. It will be remembered as the occasion on which primary emphasis shifted from the G-7, the global steering group that until now has had a monopoly on real economic decision-making power, to the G-20. Of the various substantive ways in which developing countries could and should have been given more representation in recent years, the shift to the G-20 is the first one to have actually taken place.