Despite a dearth of natural resources, the Swiss economy is among the world's most advanced and prosperous. Per capita income is virtually the highest in the world, as are wages. Trade has been the key to prosperity in Switzerland. The country is dependent upon export markets to generate income while dependent upon imports for raw materials and to expand the range of goods and services available in the country. Switzerland has liberal trade and investment policies and a conservative fiscal policy. The Swiss legal system is highly developed, commercial law is well defined, and solid laws and policies protect investments. The Swiss franc is one of the world's soundest currencies, and the country is known for its high standard of banking and financial services. Switzerland is a member of a number of international economic organizations, including the UN, the World Trade Organization, the International Monetary Fund, the World Bank, and the Organization for Economic Cooperation and Development (OECD).