In the 14th Parliament the then Speaker of the Chamber of Deputies, Pier Ferdinando Casini, appointed him as Chairman of the Foundation of the Chamber of Deputies, an office which he held until the end of that Parliament.
Napolitāno bija Eiropas Parlamenta deputāts; 5. sasaukuma laikā viņš vadīja Eiropas Parlamenta Konstitucionālo lietu komiteju. .