BSE (Bovine Spongiform Encephalopathy) is a neurodegenerative disease of cattle, included in the family of human and animal diseases called Transmissible Spongiform Encephalopathies. There are strong scientific evidences linking BSE with a new disease in humans, called variant of Creutzfeldt Jacob Disease (vCJD), that is probably acquired trough consumption of BSE - infected meat. The emergence of BSE in the European herds in the mid-1980s had a huge impact on the European animal production industry. To date, over 180.000 cases of BSE have been reported in United Kingdom, with numerous outbreaks occurring in other European Countries, including Italy. The majority of human cases (120 victims to date) have been diagnosed in UK in young individuals. The introduction of a system of active surveillance for BSE using the new rapid test in January 2001 allowed to identify its occurrence in some Countries not previously reported for BSE by passive surveillance. Among these Countries, Italy detected fifty positive cases in 2001 out of half a million rapid tests. The overall prevalence and incidence rates of BSE in Italy are low compared to the European situation. The geographical distribution of outbreaks roughly reflects the National distribution of adult cattle population, even if in some areas there is a statistically significant excess in the number of observed vs expected cases