This guide describes the records of the federal courts, as well as records of Congress and the executive branch, that are relevant to researching federal judicial history. Most federal records are held by the National Archives and Records Administration (NARA), either at NARA's main facilities in Washington, D.C., and College Park, Maryland, or at one of the National Archives' regional branches. Recent records may still be held by the government agency that created the records, or, pending their accession by the National Archives, at a Federal Records Center. Records at the National Archives are organized into "record groups," with most government departments, offices, organizations, and agencies being assigned their own record group number. The records of the U.S. district courts, for example, are in Record Group (RG) 21, while the general records of the Department of the Treasury are in RG 56, and the records of the U.S. courts of appeals are in RG 276. Each chapter of this guide directs researchers to record groups related to various aspects of judicial history, as well as to materials that document the judiciary's relationship with the other two branches of the federal government.