This thesis revolves around financial instability and banking regulation. The first chapter examines whether the disclosure of information about banks maximizes welfare in times of crisis. Contrary to conventional wisdom, we demonstrate that transparency is optimal only if banks' distress can be efficiently resolved. The second chapter provides an explanation for the observed inability of market participants to assess banks' solvency in times of crisis. We demonstrate that banks' incentives to understate losses lead to an equilibrium where no information is available in the market in times of crisis, and this makes banks take excessive risk ex-ante. The third chapter, coauthored with Philipp Ager, provides an empirical analysis of the effec...