The papers in this Symposium issue complement two other compilations of research on the multilateral trading system published in Evenett and Hoekman (2006) and Hoekman and Vines (2007) and are a final output of the UK Department for International Development supported Global Trade and Financial Architecture project. The genesis of this Symposium was a CEPR workshop hosted by the OECD in March 2012 with support from DG Research (grant: PEGGED Collaborative Projects under the EU's Seventh Framework Programme, Contract no. SSH-CT-2008-217559).