Established by the Homeland Security Act (2002), the Department of Homeland Security (DHS) was the administrative response to the terrorist attacks of September 11, 2001. The DHS coordinates most of the antiterror elements within the U.S. government in a new cabinet-level network of agencies tasked with the specific mission of preventing terrorist attacks within the United States, reducing vulnerability to terrorism, and minimizing damage from potential terrorist attacks. The Department of Homeland Security became fully operational on March 1, 2003. The DHS is divided into five directorates. Border and Transportation Security (BTS), the largest, is responsible for securing the nation’s borders and protecting its transportation systems. Agencies within the BTS include the Transportation Security Administration, the Animal and Plant Health Inspection Service, and the Federal Law Enforcement Training Center. The BTS performs security functions previously under the direction of the U.S. Customs Service and the Immigration and Naturalization Service. The Emergency Preparedness and Response Directorate (EPR) is responsible for preparing against terrorist attack and natural disasters and for overseeing necessary recoveries. The Science and Technology Directorate (S&T) is devoted to research and development necessary for preparing against and responding to potential terrorist attacks involving weapons of mass destruction. The Information Analysis and Infrastructure Protection Directorate (IAIP) identifies and assesses intelligence information from many sources, issues warnings, and recommends preventive action. The Management Directorate is responsible for management and personnel matters related to the work of the Department of Homeland Security. In addition to the five directorates, other agencies work under the umbrella of the DHS. Except in time of war or under the direct order of the president, the U.S. Coast Guard operates under the Department of Homeland Security. The U.S. Secret Service is responsible for protecting government officials from harm and the U.S. currency from counterfeiting. The Bureau of Citizenship and Immigration Services, which includes the U.S. Citizenship and Immigration Services, administers immigration policy and provides services to all immigrants. The Office of State and Local Government Coordination ensures a coordinated response in case of terrorist attack, while the Office of Private Sector Liaison enables businesses, trade associations, and other nongovernmental organizations to work directly with the DHS on any security issues. The Office of Inspector General operates independently to audit and investigate any allegations of fraud, inefficiency, or mismanagement within the Department of Homeland Security. The relative importance and particular responsibilities of the various directorates and agencies are likely to change as the Department of Homeland Security (DHS) develops.