This policy brief (PB), prepared for the G-20 Working Group on Trade, aims to provide decision-makers with a succinct review of the state of the trading system, to point to likely scenarios, and to serve as a background to or reference for the other six PBs prepared by the T20 Task Force on Trade, Investment and Globalization. The brief argues that the world trading system has been remarkably successful in many respects but that the present strain reflects causes which are deep-seat ...