DoD readiness rests on a foundation of open and available training lands where soldiers, sailors, marines, and airmen train as they fight. The health of those training lands depends on the readiness-ecosystem nexus, which supports both the training environment and natural environment in balanced co-existence. The DoD has and continues to play a vital role in sustaining many rare plant and animal species. In the United States, DoD manages approximately 25 million acres with hundreds of installations required to possess active ecosystem management plans. DoD also has the highest density of species listed as threatened or endangered (T&E) under the Endangered Species Act (ESA) of any federal land management agency. 

Due to security and range management requirements, access to military lands is limited. Military lands are sheltered from trespass, development pressures, and large-scale habitat loss. Military training activities and land use are generally compatible with endangered species management, as well. SERDP and ESTCP projects advance the management and sustainment of rare wildlife habitats are found on military installations.