Matthew Simmons, chairman and CEO of Simmons & Company International, is a prominent oil-industry insider and one of the world's leading experts on the topic of peak oil. Simmons was motivated by the 1973 energy crisis to create an investment banking firm catering to oil companies. In his previous capacity, he served as energy adviser to U.S. President George W. Bush. Matthew Simmons is a member of the National Petroleum Council and the Council on Foreign Relations. He believes a careful assessment of Saudi Arabian oil reserves is the most significant issue shaping petroleum politics. Simmons is the author of the book Twilight in the Desert: The Coming Saudi Oil Shock and the World Economy. His examination of oil reserve decline rates helped raise awareness of the unreliability of Middle East oil reserves as the published reports have never been verified.