biotech goods. The WTO is a voluntary “club” of nations, with no enforcement mechanism. It relies on members to voluntarily comply with agreements. Three overriding principles of the WTO are that members’ regulations regarding trade must be transparent, not discriminate among WTO members, and not favor domestic sellers relative to imports. The Agreement on Sanitary and Phytosanitary (SPS) Measures of the GATT recognizes that members establish their own rules for food safety and environmental protection. The WTO Web site notes that SPS regulations “must be based on science; they should be applied only to the extent necessary to protect human, animal or plant life or health; and they should not arbitrarily or unjustifiably discriminate between countries where identical or similar conditions prevail.” The Cartagena Protocol also deals with some aspects of cross-border shipments of biotech-related materials. However, major agricultural exporters, such as the United States, Australia, Canada, Argentina and New Zealand have not ratified the protocol and it does not exempt any nation from GATT obligations. Although WTO members have wide latitude in specifying trade rules to ensure food and environmental safety, they have nonetheless been subject to formal dispute. The United States and other nations have filed formal proceedings with the WTO concerning the European Communities‘ “Measures Affecting the Approval and Marketing of Biotech Products.” Their argument is that the European Union has erected barriers that are not based on the sound application of science and thereby inappropriately block importation of safe products. Related issues concerning, for example, specifics of product labeling, have not yet reached formal WTO disputes, but may be on the horizon. The dispute has important implications for horticultural biotechnology. The initial costs of apDaniel A. Sumner Director, UC Agricultural Issues Center