Domestic and international responses to bovine spongiform encephalopathy (BSE) in North America have permanently altered international market opportunities for U.S. beef. As expected, most international markets immediately banned imports of U.S. beef when the fi rst U.S. case was reported in December 2003. Beef and beef variety meat exports in 2004 fell 75 percent by volume and 79 percent by value compared with 2003 levels. By April 2005, strong demand from Mexico and the reopening of a few markets helped overcome some of the overall trade loss, but most major markets remained closed to U.S. beef (see Table 1).