USDA's Food Safety and Inspection Service (FSIS) is formulating risk assessments to identify important foodborne hazards; evaluate potential strategies to prevent, reduce, or eliminate those hazards; assess the effects of different mitigation strategies; and identify research needs. These risk assessments, in brief, empirically characterize the determinants of the presence or level of microbial contamination in vulnerable foodstuffs at various points leading up to consumption. One of the initial efforts in the undertaking is a risk assessment of the public health impact of E. coli O157:H7 in ground beef. In addition to soliciting public input, FSIS asked the Institute of Medicine (IOM) to convene a committee of experts to review the draft and offer recommendations and suggestions for consideration as the agency finalizes the document. This report presents the results of that review.