Organization of the Petroleum Exporting Countries Organization of the Petroleum Exporting Countries Organization of the Petroleum Exporting Countries Organization of the Petroleum Exporting Countries Organization of the Petroleum Exporting Countries Organization of the Petroleum Exporting Countries Organization of the Petroleum Exporting Countries Organization of the Petroleum Exporting Countries 12-member orgnization Organization of the Petroleum Exporting Countries Organization of the Petroleum Exporting Countries OPEC Organization of the Petroleum Exporting Countries Organization of Petroleum Exporting Countries