Proceedings of an OECD Workshop. Effects of productivity shocks and export restrictions on welfare and food supply in Japan”, Food Policy, Vol. The Political Economy of International Trade Law. Essays in Honor of Robert E. Hudec, Cambridge University Press, Cambridge. Paper prepared for the conference on “Challenges Facing the World Trade System” organized by J. Bhagwati, P. Krishna and A. Panagariya, Columbia University, New York, and Johns Hopkins University (SAIS), 29 September - 2 October, Washington DC.