Trade is a cornerstone concept in economics, taught in all departments both in the US and abroad. Since 1985 a number of new theoretical approaches that are essential to any graduate international trade course, and should be of interest in development economics and other fields. Here, Robert Feenstra steps beyond theory to consider empirical evidence as well. He covers all the basic material including the Ricardian and Hecksher-Ohlin models, extension to many goods and factors, and the role of tariffs, quotas, and other trade policies; material including imperfect competition, outsourcing, political economy, multinationals and endogenous growth; and new material including the gravity equation and the organization of the firm in international trade. Throughout the book, special emphasis is placed on integrating the theoretical models with empirical evidence, and this is supplemented by theoretical and empirical exercises that appear with each chapter. It is intended to bring readers to the forefront of knowledge in international trade and prepare them to undertake their own research. Both graduate students and faculty should find a wealth of topics that have previously only been covered in journal articles, and are dealt with here in a common and simple notation. In addition to known results, the book includes some particularly important unpublished results by various authors. Two appendices describe empirical methods applicable to research problems in international trade, methods that draw on (i) index numbers and (ii) discrete choice models.