Mohammed bin Salman bin Abdulaziz Al Saud (born August 31, 1985), colloquially known as MBS, is the crown prince of Saudi Arabia. He is currently serving as the country's deputy prime minister (the title of prime minister being held by his father, the king) and is also chairman of the Council for Economic and Development Affairs, chairman of the Council of Political and Security Affairs, and minister of defense – the world's youngest at the time of his appointment. He has been described as the power behind the throne of his father, King Salman. He was appointed crown prince in June 2017 following King Salman’s decision to remove Muhammad bin Nayef from all positions, making Mohammed bin Salman heir presumptive to the throne.