The massive inflow of oil revenues on account of the rise in oil prices to the member countries of the Gulf Cooperation Council (GCC) put them in an unprecedented situation. The oil revenue at the disposal of these countries was so enormous that, in addition to its deployment in the domestic economy, it had to be invested in foreign countries. However, this phenomenon slowed down with the decline in global oil prices and consequent lower inflow of oil revenues in these countries. As this book shows, this is expected to last as long as GCC countries remain a significant source of supply of oil to the global market. For these nations, their foreign investment programme has been an important tool of diversification. The book also argues that, for these countries, foreign investment has been an important strategy for preserving and expanding their oil wealth for the future.