Connect them where it hurts. The missing piece of the puzzle.

The crisis has shown that banks that are too big to fail are at the core of the international financial system. These institutions are thus at the centre of a powerful wave of re-regulation of the banking system. Overall, the proposals developed to strengthen the capacity of big banks to weather future crises, starting with Basel 3, point in the right direction, but they are missing an essential element. SIFIs have a peculiar nature. Their most salient feature is that because of their size, interconnectedness and similar strategies, a crisis of one tends to become a crisis of all. Hence, it is essential to have a mechanism in place to link them together beforehand. The paper analyzes measures that can serve this end. It then proposes a tool designed to give SIFIs a shared interest in behaving correctly, i.e. taking into account the externality implied by their very existence.