The Netherlands is a constituent country located in Western Europe and with territories in the Caribbean. It is bordered by Belgium and Germany. The Netherlands is mostly low-lying, located at the mouths of three major European rivers (Rhine, Meuse, and Schelde). The government system is a constitutional monarchy; the chief of state is the king, and the head of government is the prime minister. The Netherlands has a mixed economic system which includes a variety of private freedom, combined with centralized economic planning and government regulation. Netherlands is a member of the European Union (EU).