This book commemorates a pivotal moment in economic thought—the 50th anniversary of Alfred Eicher and Jan Kregel's groundbreaking 1975 article in the Journal of Economic Literature that boldly announced a "new paradigm in economics" and marked the first journal publication to carry the post-Keynesian label. What began as an academic declaration has evolved into a influential school of economic thought that continues to shape policy debates and theoretical frameworks worldwide. However, the story of post-Keynesian economics extends far beyond its Anglo-American origins. While existing scholarship has predominantly focused on developments in the United States and England, this comprehensive volume breaks new ground by exploring how post-Keynesian ideas emerged, adapted, and flourished across diverse global contexts. From European innovations to developments in emerging economies, this collection reveals the rich, untold history of how post-Keynesian thought took root in different intellectual and institutional environments around the world. This book will be beneficial for graduate students, economists and scholars interested in heterodox economic thought and the history of economic ideas. Policy makers and practitioners interested in alternative economic frameworks will also find valuable insights into how post-Keynesian ideas have been implemented and adapted across different national contexts. The chapters in this book were published in Review of Political Economy.