It is sometimes easy to forget in a discussion of trade, investment and sustainable development that trade and investment are actually carried out by private companies, not by governments or international organizations. Goods are bought and sold, and investment decisions made, by the private sector. A large proportion of global trade and investment is now accounted for by a small number of enormous multinational companies: 359 companies account for 40 per cent of world trade, and the world’s largest 100 companies have revenues that exceed the gross domestic product (GDP) of 50 per cent of the world’s countries. 1 If the huge economic power of these companies and the trade and investment flows they control are to be harnessed for sustainable development, it is vital to understand what influences multinational corporations.