Democratic Drain links two of the most compelling topics of our time: immigration and democracy. With a blend of in-depth interviews and data analysis across 149 countries, Justin Gest explores how global migration filters people with liberal democratic values out of authoritarian spaces, enabling democratic backsliding around the world. At a global scale, the correlation between migratory choices and political values introduces a new reason why authoritarian countries may have struggled to democratize in the decades since the end of the Cold War – a period when flows of international migrants have grown so significantly, populism has spread, and authoritarians' resolve has steadily hardened. At a time when the world is increasingly sorting into democratic and undemocratic spaces, Gest's timely and innovative analysis raises important political and policy questions about how democracies might compensate for the inadvertent effects of global human mobility.