Technical Abstract: The objective of this study was to determine the length of time that E. coli O157:H7 survives on the hides of cattle. Extensive research has been conducted and is on-going to identify and develop novel pre- and post-harvest intervention strategies to reduce E. coli O157:H7 from live cattle and processed carcasses. If reduction of E. coli O157:H7 levels in feces can be achieved through pre-harvest intervention, it is not known how long it would take for such reductions to be seen on the hide. In order to design effective pre-harvest intervention strategies, it is necessary to determine the duration of survival of E. coli O157:H7 following a hide contamination event. Previous studies have shown that E. coli O157:H7 can persist in a variety of matrices for greater than 100 days. The survival of E. coli O157:H7 on the hides of living cattle is not well understood. In the study presented herein, cattle were housed in a manner to minimize or prevent hide contamination events. Through prevalence determination and isolate genotyping with pulsed field gel electrophoresis, E. coli O157:H7 survival on the hides of live cattle was determined to be short lived with an approximate duration of nine days or less. The results of this study suggest that any preharvest interventions that are to be administered at the end of the finishing period should be given approximately nine days before the cattle are presented for processing, to allow sufficient time for E. coli O157:H7 levels on the hide to be reduced.