‘Openness and the Output-Inflation Tradeoff’ Christopher Bowdler Nuffield College, University of Oxford Abstract: Standard open economy models predict that openness to trade should exert a positive effect on the slope of the output-inflation tradeoff, or Phillips curve, but such a proposition finds very little support in the existing empirical literature. We propose a new test of this hypothesis based on new measures of the slope of the Phillips curve and more general cross-country regression models. The results indicate some support for the standard theoretical prediction, but it is confined to those countries that have maintained floating exchange rate regimes. Keywords: Openness, Inflation, Phillips curve.