Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online.The United States Secret Service is a United States federal law enforcement agency that falls under the United States Department of Homeland Security. The sworn members are divided among the Special Agents and the Uniformed Division. Until March 1, 2003, the Service was part of the United States Department of Treasury. The Secret Service began as an agency for the investigation of crimes related to the Treasury, and then evolved into the United States'' first domestic intelligence and counterintelligence agency. Many of the previous missions of the Secret Service were later taken over by subsequent agencies such as the FBI, ATF, and IRS and Naval Criminal Investigative Service.