The IMF Working Papers series is designed to make IMF staff research available to a wide audience. Almost 300 Working Papers are released each year, covering a wide range of theoretical and analytical topics, including balance of payments, monetary and fiscal issues, global liquidity, and national and international economic developments.
This paper develops a model of the lender of last resort. It provides an analytical basis for “too big too fail” and a rationale for “constructive ambiguity”. Key results are that if contagion (moral hazard) is the main concern, the Central Bank (CB) will have an excessive (little) incentive to rescue banks and the resulting equilibrium risk level is high (low). When both contagion and moral hazard are jointly analyzed, the CB’s incentives to rescue are only slightly weaker than with contagion alone. The CB’s optimal policy may be non-monotonic in bank size.