The Smithsonian Institution (pronounced /smɪθˈsoʊnɪən/) is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its shops and its magazines. Most of its facilities are located in Washington, D.C., but its 19 museums, zoo, and nine research centers include sites in New York City, Virginia, Panama, and elsewhere.It has over 136 million items in its collections,publishes two magazines named Smithsonian (monthly) and Air & Space (bimonthly), and employs the Smithsonian Police to protect visitors, staff, and the property of the museums. The Institution's current logo is a stylized sun.
The Smithsonian Institution is established as a trust instrumentality by act of Congress, and it is functionally and legally a body of the federal government. More than two-thirds of the Smithsonian's workforce of some 6,300 persons are employees of the federal government. The Smithsonian is represented by attorneys from the United States Department of Justice in litigation, and money judgments against the Smithsonian are also paid out of the federal treasury.

The legislation that created the Smithsonian Institution (approved by Congress Aug. 10, 1846) called for the creation of a Board of Regents to govern and administer the organization. This 17-member board meets at least four times a year and includes as ex officio members the Chief Justice of the United States and the Vice President of the United States. The nominal head of the Institution is the Chancellor, an office which has traditionally been held by the Chief Justice. In September 2007, the Board created the position of Chair of the Board of the Board of Regents, a position currently occupied by Patricia Q. Stonesifer of Washington State.

Other members of the Board of Regents are three members of the U.S. House of Representatives appointed by the Speaker of the House; three members of the Senate, appointed by the President pro tempore of the Senate; and nine citizen members, nominated by the Board and approved by the Congress in a joint resolution signed by the President of the United States.Regents who are representatives and senators serve for the duration of their elected term. Citizen Regents serve a maximum of two six-year terms. Regents are compensated on a part-time basis. The chief executive officer of the Smithsonian is the Secretary, who is appointed by the Board of Regents. There have been 12 Secretaries since the Smithsonian was established. The Secretary also serves as secretary to the Board of Regents but is not a voting member of that body. The Secretary of the Smithsonian has the privilege of the floor at the United States Senate.