Tax havens are low-tax jurisdictions that offer businesses and individuals opportunities for tax avoidance. The 45 major tax haven countries in the world today are small, affluent, and generally well governed. They attract disproportionate shares of world foreign direct investment, and, largely as a consequence, their economies have grown much more rapidly than the world as a whole since the 1980s. The effect of tax havens on economic welfare in high-tax countries is unclear, though the availability of tax havens appears to stimulate economic activity in nearby high-tax countries.