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).
President of Italy
The 1948 Constitution does not put any term limit on the presidency, although until 2013 no President ever ran for a second term. On 20 April 2013, President Giorgio Napolitano agreed to run for a second term in an attempt to break the parliamentary deadlock in the 2013 presidential elections and was duly re-elected that same day. However, he made it clear that he would not serve his full term and retired in January 2015.