We analyse UK monetary policy using monthly data for 1992-2010. We have two main findings. First, the Taylor rule breaks down after 2007 as the estimated response to inflation falls markedly and becomes insignificant. Second, policy is best described as a weighted average of a "financial crisis" regime in which policy rates respond strongly to financial stress and a "no-crisis" Taylor rule regime. Our analysis provides a clear explanation for the deep cuts in policy rates beginning in late 2008 and highlights the dilemma faced by policymakers in 2010-11.