The author has virtually incomparable experience in both providing trade policy advice to more than 25 countries on behalf of the World Bank and also publishing quality journal articles in most of those cases. In this volume, he focuses on his work on: (i) trade policies for countries making the transition from planned to market economies; (ii) his trade policy guideline papers for the World Bank on trade policies for poverty alleviation, uniform tariff policy, adjustment costs of trade liberalization, exchange rate overvaluation, globalization and technology transfer and rules of thumb on regional trade policies; (iii) multilateral, dynamic and environmental issues in trade policy using computable general equilibrium models; (iv) trade policy of the United States in the auto and steel industries; and (v) mathematical methods for modeling. The papers show an unusual combination of policy relevance, advice and impact, with rigor and international trade theory insights.The papers in this volume have appeared in many of the economics profession's more prestigious journals, including Econometrica, Review of Economic Studies, Quarterly Journal of Economics, Economic Journal, the Journal of International Economics, International Economic Review, European Economic Review, Canadian Journal of Economics, Economic Inquiry, the Journal of Comparative Economic, Review of International Economics, World Economy, the Southern Economic Journal, the World Bank Economic Review, the Japanese Economic Review and the Latin American Journal of Economics. In this book, the author elaborates on the articles by discussing some of the policy contexts for the requests for the work from developing and transition countries to the World Bank, the key trade theory or policy insights, policy recommendations and conclusions and the policy impacts.