A set of related entities that share one or more characteristics and define the semantic of a specific field. This concept is essential to the next definition. This concept has many ERM applications; for example: • A security domain groups assets with the same security level that fall under the jurisdiction of one security policy. • This White Paper develops the concepts of risk management domain and mitigation domain A risk management domain groups entities that share one or more characteristics relevant to risk management or security, while a mitigation domain groups assets and actions that together mitigate risk in one or more risk management domains.