How do democracies fail? Ranging across geography and time, How to Save a Constitutional Democracy presents a comprehensive account of the mechanisms through which democratic rule has come undone. From the beginning of the twentieth century, to the global resurgence of populism, it explains how the pathway of democratic failure has evolved. Turning to the present, it analyzes the ways in which many constitutions are vulnerable to democratic backsliding—and as importantly proposes an agenda of reforms that might stymie that process.