After high inflation is defeated in the next year or two, the world risks returning to the excessive unemployment of the decades before 2020. Central banks will therefore need to put less faith in estimates of sustainable employment based on simple linear models and adopt a more aggressive policy approach than they have in the past—one that regularly probes the limits of noninflationary job creation. In addition, a small rise in the inflation target, from 2 percent to 3 or 4 percent, would make it much easier for central banks to maintain maximum employment.