A diplomat (from Ancient Greek: δίπλωμα; romanized diploma) is a person appointed by a state or an intergovernmental institution such as the United Nations or the European Union to conduct diplomacy with one or more other states or international organizations. Diplomats are the oldest form of any of the foreign policy institutions of a state, predating by centuries foreign ministers and ministerial offices. They usually have diplomatic immunity, and in their official travels they usually use a diplomatic passport or, for UN officials, a United Nations laissez-passer.