Sterling money markets are a critical part of the plumbing of the UK financial system. They act as the main conduit for short-term borrowing and lending between banks, and a whole range of other institutions, financial and non-financial. And the ebb and flow of activity in sterling money markets is also crucial to the Bank of England as the first stage in the transmission mechanism of monetary policy, linking changes in the Bank’s policy rate – Bank Rate – to activity and prices in the wider economy. So when things go wrong in this market, as they did during the financial crisis, the effects reach into every part of the UK economy and, given the significant role of international banks in London, beyond. So what happened in the autumn of 2008, and why?