In 1876, Carl Menger, then a young professor at the University of Vienna, was asked to teach the principles of political economy to the 17-year-old only son of Emperor Francis Joseph. Rudolf's notebooks to these lectures, corrected by Menger, are a record of what Menger thought worth teaching to the heir. They are a document of classical economic liberalism and cast new light on Menger's own theoretical discoveries. In this volume, Rudolf's notebooks are published both in German and in an English translation. Apart from a detailed English introduction, both versions are annotated by a Menger expert, who has traced the surprising sources of this text, passage by passage.