Japan is a constitutional monarchy where the power of the Emperor is very limited. As a ceremonial figurehead, he is defined by the constitution as "the symbol of the state and of the unity of the people." Power is held chiefly by the Prime Minister of Japan and other elected members of the Diet, while sovereignty is vested in the Japanese people.[55] Akihito is the current Emperor of Japan; Naruhito, Crown Prince of Japan, stands as next in line to the throne.