This research effort is undertaken to determine the impact that one hospital’s diversion status has on other hospitals in a region and the strength of these interactions. The conditional probability of one hospital going on diversion given that another is already on diversion is evaluated. Based on this analysis, the strength of interactions among the hospitals is established. Through statistical analyses of historical data, the strength of the mutual effects of diversion among a collection of hospitals is determined. These effects are mutual if one hospital’s diversion status affected another’s, then the reverse was also true. The intensity of these interactions between hospitals is varied, some being stronger than others. The model illustrates an approach to studying the cascading effects of diversion among hospitals in a region. This is important, because the status of any hospital in a region can signal the likelihood of impending diversion in every other hospital in the region. This allows actions that might prevent the occurrence of diversion or mitigate the cascading effects of Emergency Medical Systems diversion.