The book analyzes the evolution of the concept of comparative advantage from the eighteenth century to the present day. It examines the origins of the concept of comparative advantage, its current status within economic thought and its validity in today's global economy.This comprehensive book outlines the theories of trade and the interpretations of comparative advantage associated with, among others, the Mercantilists, Smith, Ricardo, Torrens, Longfield, Mill, Marshall, Pareto, Haberler, Heckscher, Ohlin and Samuelson, as well as present day trade theorists. A chapter is devoted to Hamilton, Rae and List, who interpreted comparative advantage dynamically by advocating its creation. The book breaks new ground by reinterpreting the theories of trade associated with prominent economists such as Ricardo, and drawing attention to valuable but lesser known contributions. It considers the new trade theory from the past two decades as a legitimate successor to the dynamic views of comparative advantage of the classical economists. This book will be required reading for students and academics with an interest in the history of economic thought and the economics (or theory) of international trade.