The masterpiece first appeared in German in 1940 and then disappeared, only to reappear in English in 1949. It was a sensation, the largest and most scientific defense of human freedom ever published.
As is well known, Mises's book is the best defense of capitalism ever written. It covers basic economics through the most advanced material. Reading this book is the best way you could ever dream up to learn economics. Every attempt to study economics should include a thorough examination of this book.
Robert Murphy's study guide for Human Action is available here.
Ludwig von Mises was the acknowledged leader of the Austrian school of economic thought, a prodigious originator in economic theory, and a prolific author. Mises's writings and lectures encompassed economic theory, history, epistemology, government, and political philosophy. His contributions to economic theory include important clarifications on the quantity theory of money, the theory of the trade cycle, the integration of monetary theory with economic theory in general, and a demonstration that socialism must fail because it cannot solve the problem of economic calculation. Mises was the first scholar to recognize that economics is part of a larger science in human action, a science that he called praxeology.
Auburn, Alabama: Mises Institute, 1999. Re-issue of the classic 1949 Edition with new introduction and expanded index, with premium bindings and papers.