Oath of office of the president of the United States

President Barack Obama being administered the oath of office by Chief Justice John Roberts for the second time, on January 21, 2009.

The oath of office of the President of the United States is an oath or affirmation required by the United States Constitution before the president of the United States begins the execution of the office.

Oath

• I do solemnly swear (or affirm) that I will faithfully execute the Office of President of the United States, and will to the best of my Ability, preserve, protect and defend the Constitution of the United States.