Andrew Stuart Fastow (born December 22, 1961) is an American convicted felon and former financier who was the chief financial officer of Enron Corporation, an energy trading company based in Houston, Texas, until he was fired shortly before the company declared bankruptcy. Fastow was one of the key figures behind the complex web of off-balance-sheet special purpose entities (limited partnerships which Enron controlled) used to conceal Enron's massive losses in their quarterly balance sheets. By 