This working paper from the International Monetary Fund looks at a global system comprising large banks from a range of countries to assess the sources of systemic risk and contagion from individual institutions to the system as a whole. It argues that short-term wholesale funding plays the “major role” in spreading systemic risk to international financial markets, thus providing support for international liquidity rules such as the Basel Committee’s Liquidity Coverage Ratio and Net-Stable-Funding Ratio. However, the authors find little evidence to suggest that within a system of large banks, either relative size or leverage is a helpful measure for locating potential risks.