All executive authority is vested in the monarch, and royal assent is required for parliament to enact laws and for letters patent and Orders in Council to have legal effect. However, the monarch's authority is subject to the conventional stipulations of constitutional monarchy, and her direct participation in these areas of governance is limited. Most of the related powers are instead exercised by the elected members of parliament, the ministers of the Crown generally drawn from amongst them, and the judges and justices of the peace. Other powers vested in the monarch, such as the appointment of a prime minister, are significant, but are treated only as reserve powers and as an important security part of the role of the monarchy.