Major economies such as the United States, European Union, Japan, and even China have shifted trade negotiating emphasis toward 'mega-regional' agreements, including the Trans-Pacific Partnership (TPP), the Transatlantic Trade and Investment Partnership (TTIP), and the Regional Comprehensive Economic Partnership (RCEP). This paper explores why countries have chosen to pursue mega-regionals, what is likely to be contained in the agreements, and some of their potential implications for the multilateral trading system under the World Trade Organization (WTO). I call for revisiting the historical approach of introducing plurilateral and critical mass agreements -that would cover some of the mega-regionals' new provisions -into the WTO so as to avoid a more substantial, long-run erosion of the relevance of the nondiscriminatory system. I also highlight potential reforms to the WTO's dispute settlement procedure that are required to strengthen its already prominent role.The major economies have shifted trade negotiating emphasis toward mega-regional agreements. The emergence of three sets of negotiations -the Trans-Pacific Partnership (TPP) agreement among Australia, Canada, Japan, Mexico, the United States, and seven other countries; the Transatlantic Trade and Investment Partnership (TTIP) negotiations between the United States and the European Union (EU); and China's pursuit of the Regional Comprehensive Economic Partnership (RCEP) negotiations -raises a host of short and long-term questions for the multilateral trading system and the World Trade Organization (WTO).The General Agreement on Tariffs and Trade (GATT) and WTO established a multilateral system for trade that has remained largely unchanged since 1995. The desire to write new rules to address potential nontariff barriers to tradecovering public health and product safety standards, labor and the environment, international investment, digital trade and e-commerce, and state-owned enterprises -is an important driver of both the TPP and TTIP negotiations. 1 These new regional trade agreements (RTAs) pose some potential threats to the multilateral system. First, they are discriminatory agreements that provide preferences to insiders at the expense of outsiders, and this could lead to economic distortions or a fracturing of global trade into competing blocks. Second, many of these issue areas are being brought into a trade agreement for the first time. The full consequences of this policy decision -including for the WTO -are still largely unknown.However, direct steps can be taken to help mitigate such concerns. One is to return to plurilateral and critical mass agreements to bring some of the mega-regionals' important new disciplines into the WTO. However, reforms to the WTO's dispute settlement procedures are also needed to further strengthen and sustain its most prominent, dayto-day function.
The multilateral trading systemThe GATT was established in 1947, and it shepherded the multilateral trading system until it was replaced by the WTO in 1995. O...