Interagency, International, and Environmental Services (IIS) is the U.S. Army Corps of Engineers Philadelphia District program providing technical assistance to non-Department of Defense (DoD) federal agencies, state and local governments, tribal nations and other entities. Most IIES work is funded on a reimbursable basis. USACE provides engineering and construction services, environmental restoration and management services, research and development assistance, management of water and land related natural resources, relief and recovery work, and other  management and technical services. Customers include the EPA, FEMA, Coast Guard, National Park Service, and the Federal Aviation Administration.