Verocytotoxin-producing Escherichia coli (VTEC), and in particular, stains of serogroup O157, have emerged as significant pathogens causing a range of severe and potentially fatal illnesses. The European Union has recognized the threat posed by E. coli O157:H7, and the need to devise control strategies. Thus, the EC funded a Concerted Action Project, and this book compiled for the above project integrates contributions from a number of experts in various disciplines, and provides a comprehensive overview of the current status of research on VTEC.