Jennifer Castle, David Hendry Three stylised structural changes have been underway since the end of 1980s. First, the Phillips curve flattened. Figure 1 reports rolling estimates of the slope of the Phillips curve based on a panel of six advanced economies. The large swings in output and unemployment since the Global Crisis put the debate on the ‘elusive’ Phillips curve under the spotlight, as a key ingredient to the ‘missing deflation’ and ‘missing inflation’ puzzles (Hall 2013, Coibion and Gorodnichenko 2013, Constancio 2015, Williams 2010 among many others). Yet the flattening was already well underway when the Global Crisis hit – it is widely acknowledged that it dates back to the end of the 1980s (Blanchard 2016, Del Negro et al. 2020).