This book clarifies the specific nature of the Austrian theory and restores the unity and open-mindedness of the Austrian school in general. The intention is not to offer a collection of different or parallel ideas, but rather to retrace, from a pedagogical and constructive perspective, the various stages of the construction of a well-founded theoretical edifice: from Ludwig von Mises to Murray Rothbard, from Friedrich Hayek to Israel M. Kirzner and from Lachmann to Lavoie. The book is a reconstitution of the way Austrian ideas and concepts organize themselves in a common structure.Providing a clear distinction between economic analysis and doctrine, this in-depth and unified theoretical book will be valuable to postgraduate students and researchers of economics. It is a great introduction to major Austrian theories including money, the firm, cognitive psychology, comparative economic systems and economic information.