Unlike Western royal families, the Saudi Monarchy has not had a clearly defined order of succession. Historically, upon becoming King, the monarch has designated an heir apparent to the throne who serves as Crown Prince of the Kingdom. Upon the King's death the Crown Prince becomes King, and during the King's incapacitation the Crown Prince, likewise, assumes power as regent. Although other members of the Al Saud hold political positions in the Saudi government, it is only the King and Crown Prince who legally constitute the political institutions.