This book deals with one of the most interesting developments to have occurred in trade theory for some time. It throws light on a number of important questions such as: the role of R & D, the nature of gains from trade, the part played by scale economies, and the arguments for intervention. The overall picture which emerges advances trade theory vis-a-vis the Hecksher-Ohlin paradigm which has dominated textbooks for so long, and allows the reader to obtain some novel insights into the arguments about trade impinging on imperfectly competitive markets.