To many observers, the long-lasting, underwhelming performance of growth, employment and investment suggests that something fundamental has changed with the way advanced economies’ macroeconomies are working. One leading explanation – the notion of ‘Secular Stagnation’ – has gained traction among some economists and policymakers while being rejected by others. This column opens a Vox Debate on Secular Stagnations which will involve frequent, invited ‘Lead Commentaries’ on all issues surrounding concept and its implications for policy, analysis and research.