The city of Paris is headed by an elected mayor. The mayor is in charge of the police force, which is headed by the préfet, and works with the town halls of the 20 arrondissements of Paris. The coat of arms of the city was created in 1210 featuring a boat from the watermen's guild. The motto Fluctuat nec Mergitur is the Latin for "buffeted by waves but does not sink" and was added in the sixteenth century. The Regional Council and the Economic and Social Committees govern any local problems. The most influential political parties are the Communist Party and the Socialist Party. The national government is a coalition government comprised of the various political parties.