9  SDRs could catalyze that change by facilitating any desired reserve diversification. Establishing an enhanced substitution account at the IMF, on a temporary basis, would allow large reserve holders to exchange U.S.dollar reserves for SDR-denominated securities, thereby diversifying their portfolios.
With the IMF bearing the risk of changes in the U.S.-dollar exchange rate, an appropriate burden-sharing arrangement among its members would have to be agreed upon. A substitution account would create considerable moral hazard, since reserve holders would be tempted to engage in further accumulation. In addition, a substitution account would not address the fundamental asymmetry of the adjustment process.