One key feature of the recent crisis was the heavy reliance on short-term sources of funds to purchase long-term assets, which led to a poor match between the maturity structure of the firms’ assets and liabilities. Such maturity transformation is inherently fragile and leaves institutions and entire markets susceptible to runs. Indeed, a regulatory, supervisory, and insurance framework was created during the Great Depression to counter this problem at depository institutions. However, in recent years a significant amount of maturity transformation took place outside the traditional banking system – in the so-called shadow  14  BIS Review 16/2010  banking system – through the use of commercial paper, repurchase agreements, and other instruments. Our ability to monitor the size and extent of maturity transformation has been hampered by the lack of high-quality and consistent data on these activities. Better data on the sources and uses of maturity transformation outside of supervised banking organizations would greatly aid macro-prudential supervision and systemic risk regulation. Another feature of the recent crisis was the extensive use of leverage, often in conjunction with maturity transformation. The consequences of this combination were dramatic. When doubts arose about the quality of the assets on shadow banking system balance sheets, a classic adverse feedback loop ensued in which lenders were increasingly unwilling to roll over the short-term debt that was used as funding.

14  Nyberg (2010) provides more discussion of macroprudential regulation and regulation reform. BIS Review 16/2010  7  significant social costs. I find it helpful to conceptually distinguish financial-stability policy from monetary policy. Different economic policies and policy areas, such as fiscal policy, labor market policy, structural policies to improve competition, etc., can be distinguished according to their objectives, the policy instruments that are suitable for achieving the objectives, and the authority or authorities controlling the instruments and responsible for achieving the objectives. Monetary policy in the form of flexible inflation targeting has the objective of stabilizing both inflation around the inflation target and resource utilization around a normal level. The suitable instruments are under normal circumstances the policy rate and communication, including possibly a published policy-rate path and a forecast of inflation and the real economy. In times of crisis, as we have seen during the current crisis, other more unconventional instruments can be used, such as fixed-rate lending at longer maturities, asset purchases and foreign-exchange intervention to prevent currency appreciation. The authority responsible for monetary policy is typically the central bank. Financial-stability policy has the objective of maintaining or promoting financial stability. The available instruments are under normal circumstances supervision, regulation and financialstability reports with analyses and leading indicators that may provide early warnings of stability threats. In times of crisis, there are instruments such as lending of last resort, variable-rate lending at longer maturities, special resolution regimes for financial firms in trouble, government capital injections and so forth.