An inauguration is a ceremony of formal investiture whereby an individual assumes an office or position of authority. The term is usually used in reference to a politician's assumption of the duties of head of state or head of government (e.g. "the President's inauguration"). Traditionally, the inauguration of the President of the United States is on the 20th of January after the election.

Political inaugurations often have lavish ceremonies, in which the politician publicly takes his or her oath of office in front of a large crowd of spectators.

See also: coronation, Inauguration Day