Positioning and propaganda in the lead-up to the recent G20 meeting in London are at last focusing attention on the role reserve currencies play and the dollar in particular. But change is going to be very hard to achieve. China has been in the forefront of this by arguing for a greater role for International Monetary Fund units of account, Sor pecial Drawing Rights (SDR) and a big new issue of SDRs. It has also begun to prepare the ground for its currency, the yuan, to play a role by agreeing currency swap deals with central banks of several countries including Malaysia , Indonesia and Argentina. And it has publicly raised concerns about the safety of its US investments in the wake of massive bank bail-out and stimulus deficits to which Washington is committed.