Official Facebook page of Prince George's County Office of Emergency Management. The Office of Emergency Management falls under the Office of Homeland Security and is responsible for the coordination of all County agencies, private organizations, businesses, persons, and other counties, cities and political subdivisions. The mission for the Office of Emergency Management is to coordinate and sustain homeland security and emergency management operations that effectively support, mitigate, protect against, prepare for, respond to, and recover from natural, technological, or manmade emergencies or disasters, including terrorism.