We present a signalling theory of Quantitative Easing (QE) at the zero lower bound on the short term nominal interest rate. QE is effective because it generates a credible signal of low future real interest rates in a time consistent equilibrium. We show these results in two models. One has...

In previous work (Eggertsson and Woodford, 2003), we characterized the optimal conduct of monetary policy when a real disturbance causes the natural rate of interest to be temporarily negative, so that the zero lower bound on nominal interest rates binds, and showed that commitment to a...