Practioner's Abstract: Mad cow disease has caused two disruptions in European beef markets--first in the U.K. in 1996 following the announcement of a link to new variant Creutzfeldt-Jacob Disease in humans, and the second in late 2000 following the discovery of "homegrown" cases of the disease in Germany and Spain. In September 2001 the disease was discovered in Japan where it also resulted in an immediate and substantial reduction in beef demand. The disease has not been found in the U.S. but the current scope of detection efforts provides little assurance that it does not exist at a very low level. The U.S. has taken a number of precautionary measures to reduce both the risk of importing the disease and the risk of the disease spreading if it were to appear. Those measures include a ban on the feeding of ruminant protein to ruminants--a measure that the General Accounting Office concluded was not being adequately enforced and which failed to halt the disease in the U.K. We present an overview of BSE in the U.K., the EU, and Japan and present an argument for implementing additional precautionary measures in the U.S.