For several years, there has been a tension between differing philosophies of General Agreement on Tariffs and Trade (GATT) dispute settlement. Commentators have taken different views on whether the system was fundamentally based on an arbitration or a judicial model. The Understanding on Rules and Procedures Governing the Settlement of Disputes (DSU), Annex II to the Marrakesh Agreement Establishing the World Trade Organization (WTO Agreement), represents the first extensive, negotiated agreement revitalizing the dispute settlement system in the history of the General Agreement. It represents nothing less than a complete reform of the GATT dispute settlement system. What is remarkable is that it is the product of extensive multilateral negotiations. In the past, modifications were made to the system on an incremental, case-by-case basis. Since the GATT came into existence in 1948, Articles XXII and XXIII have formed the basis of the dispute settlement mecha-nism. They are very sparse provisions, and most of the procedures that have come to characterize the pre-WTO GATT system have evolved over time as a result of experience in specific cases. Some of these procedural improvements were codified in Decisions and Understandings negotiated at various points in GATT history, but none were as comprehensive as the DSU.