Twenty-second Amendment to the United States Constitution
Some argue that the 22nd Amendment and 12th Amendment bar any two-term president from later serving as vice president as well as from succeeding to the presidency from any point in the presidential line of succession. Others contend that the original intent of the 12th Amendment concerns qualification for "service" (age, residence, and citizenship), while the 22nd Amendment, concerns qualifications for "election", and thus (strictly applying the text) a former two-term president is still eligible to "serve" as vice president (neither amendment restricts the number of times an individual can be elected to the vice presidency), and then succeed to the presidency to serve out the balance of the term (though prohibited from running for election to an additional term).
United States presidential transition
The Presidential Transition Act of 1963 , as amended (by the Presidential Transitions Effectiveness Act of 1998 , Presidential Transition Act of 2000 , and Presidential Transitions Improvements Act of 2015 ), established formal mechanisms to facilitate presidential transitions. Specifically, the act directs the Administrator of General Services to provide facilities, funding of approximately five million dollars, access to government services, and support for a transition team, and to provide training and orientation of new government personnel and other procedures to ensure an orderly transition.