Free Trade: Old and New Challenges
分析了自由贸易理论与政策面临的旧挑战（如要素市场与产品市场不完美）和新挑战（如公平贸易要求及对富裕国家低技能工人贫困化的担忧）。
The paper analyses the old and new challenges to the theory and policy of free trade. The old challenges have sought to undermine the case for free trade by citing one or another type of market imperfection. Thus, the postwar period has seen two such challenges: Factor market imperfections were analysed in the 1950s to 1970s, product market imperfections in the 1980s. The new challenges are twofold. One comes from the demands for fair trade as a precondition for free trade; the other, from the concern that free trade, while efficient, immiserises the unskilled in the richer countries.