The GATT, which later became the WTO, has contributed to the expansion and activation of world trade by assisting trading partners to establish and enforce international trade rules through multilateral trade negotiations. Currently negotiations for new trade rules are contironing by launching Doha Round. This review intends to promote understanding of a basic analytical framework, upon which constructive debates and research have been conducted about the role of the WTO in the world trade regime. To achieve this goal, we provide a review of recent theoretical developments in studies on the role of the WTO regarding trade negotiations and rule enforcement, based on a commonly used model of trade in the literature. With respect to trade negotiations, we review a study of the effect of the reciprocity principle and most favored nation clause of the WTO on the outcome of trade negotiations and analyze the race-to-the-bottom concerns that the exclusive focus of the WTO on tariff negotiations will promote deterioration of environmental and labor standards. Regarding the rule of enforcement, we introduce the repeated game framework that is often used in the analysis of international trade rule enforcement, then discuss the studies on the role of safeguard provisions and the dispute settlement procedure of the WTO.