Description: Contemporary ERM has moved from an event-based view of risk to a hierarchical, systems-based approach. In order to operationalize such an approach, a methodology is proposed in this paper that draws on phylogenetic approaches that have been successfully developed for biological evolution. The technique and process provide an insight into the lineage, pace and impact of external conditions on the evolution of risks. They also provide a unique and rational classification of risk in an enterprise that can be used to optimize risk management resources. An example of a fictitious insurance company is used to illustrate the approach. Presented at 2010 Enterprise Risk Management Symposium, Society of Actuaries, April 12-15, 2010.