Members of the Imperial family, excluding consorts of Imperial Princes and Princes, who have reached the age of majority are qualified to assume the role of regent and to vicariously execute state affairs on an extraordinary basis (Article 17 of the Imperial House Act and Article 2 of the Act for Extraordinary Vicarious Execution of State Affairs).
親王妃・王妃を除く成年皇族は摂政就任資格と国事行為臨時代行就任資格を有する（皇室典範17条・国事行為の臨時代行に関する法律2条）。