This Book introduces the conflict between international trade and environmental protection and put forwards the sustainable development as the solution to the conflict. A leading case "Dispute Settlement Panel Report on United States Restrictions on Imports of Tuna" is enclosed for reference. The table of the contents of the Book: 1. Trade and Environment 2. An Introduction to International Trade Institution --- GATT/WTO 3. Trade and Environment: An Update on the GATT Agenda 4. Trade and Environmental Protection after Uruguay Round 5. Free International Trade and Environmental Protection: Irreconcilable Conflict? 6. Trade and Environment as Partners in Sustainable Development 7. International Trade and Environment: An Additional Non-Tariff Barrier against the Developing Countries' Trade? 8. Leading Case: Dispute Settlement Panel Report on United States Restrictions on Imports of Tuna (I) 9. Leading Case: Dispute Settlement Panel Report on United States Restrictions on Imports of Tuna (II) 10. Leading Case: Dispute Settlement Panel Report on United States Restrictions on Imports of Tuna (III) 11. Leading Case: Dispute Settlement Panel Report on United States Restrictions on Imports of Tuna (IV) 12. Leading Case: Dispute Settlement Panel Report on United States Restrictions on Imports of Tuna (V)