The Environment elements are the passive elements in the situation-independent part of the Unconventional Conflict Ontology. The Environment ontology has five categories, 21 subcategories, and 179 Environment classes. Figure 5.1 provides an illustration of the passive environment. This ontology illustrates the need for an ontology, rather than a taxonomy: one of the natural Environment classes is FireOrWildfire, which can be natural or man-made, requiring two parents at the subcategory level. This chapter describes the organization of the Environment Ontology and all of its elements, along with the types of Metrics associated with each element.