The Central Intelligence Agency was created in 1947 with the signing of the National Security Act by President Harry S. Truman. The act also created a Director of Central Intelligence (DCI) to serve as head of the United States intelligence community, act as the principal adviser to the President for intelligence matters related to the national security, and serve as head of the Central Intelligence Agency. The Intelligence Reform and Terrorism Prevention Act of 2004 amended the National Security Act to provide for a Director of National Intelligence who would assume some of the roles formerly fulfilled by the DCI, with a separate Director of the Central Intelligence Agency. One Agency. One Community. An Agency unmatched in its core capabilities, functioning as one team, fully integrated into the Intelligence Community.