Lender of last resort: A new role for an old instrument

The global financial crisis and the sovereign debt crisis in Europe have redefined the functions of the lender of last resort (LOLR). First, they have placed the LOLR at the intersection of monetary policy, fiscal policy, supervision, and regulation of the banking industry. Second, they have given regulatory authorities the additional responsibility of monitoring the interbank market. Third, they have extended the LOLR role to cover the possible bailout of non-bank institutions, including sovereign countries. This chapter explores the link between the theoretical models of the banking industry and the unprecedented policies displayed in the aftermath of the crisis. We begin by examining the justification of LOLR in a simplified framework where only liquidity shocks arise, to move to a setting where liquidity shocks cannot be disentangled from solvency ones. We then study contagion in the interbank market and systemic risk, two pathologies due to the imperfections of the financial markets, and we discuss the issues raised by the implementation of the LOLR policy within the safety net.