Presidential succession refers to the process by which a new president is selected if the current president can no longer serve due to death, resignation, or removal from office. The United States Constitution outlines this process, primarily in the 25th Amendment, which establishes the order of succession and procedures for filling a vacancy. The line of succession begins with the Vice President, followed by the Speaker of the House, the President pro tempore of the Senate, and then the members of the Cabinet in the order their departments were created. This ensures continuity of government and leadership during unforeseen circumstances.