Aruba is an island in southern Caribbean Sea located off the coast of Venezuela. Together with Bonaire and Curacao, the three are referred to as the ABC islands. The geography of Aruba is flat with a few hills and no rivers. The government system is a parliamentary democracy. Aruba is a constituent country of the Netherlands; the chief of state is the Queen of Netherlands and the head of government is the Prime Minister of Aruba. Due to its size and dependence on imports, Aruba is an open-market economy in which the prices of goods and services are determined in a free price system.