This book assesses the full impact of oil windfalls on six developing producer countries - Algeria, Ecuador, Indonesia, Nigeria, Trinidad and Tobago, and Venezuela. This is the first time that the issue has been systematically analysed and related to economics policies and underlying macroeconomic characteristics. The book adopts a broad approach, blending institutional and political aspects with quantitative analysis which includes the results of sophisticated model simulations. It presents new information on how oil discoveries have been used by producer governments, and analyses of the consequences. Finally it concludes that much of the potential benefit to producers has been dissipated, and explains why producers may actually end up worse off despite revenue gains.