Andersen – one of the world's five leading accounting firms - was Enron's auditor.
Andersen's role in the Enron affair has brought the once prestigious accounting firm to its knees.
Its job was to check that the company’s accounts were a fair reflection of what was really going on. As such, they were the first line of defence in the case of any fraud or deception.
When the scandal broke, as the government began to investigate the company’s affairs, Andersen’s chief auditor for Enron, David Duncan, ordered the shredding of thousands of documents that might prove compromising.
Andersen dismissed Mr Duncan, but insisted that the firm did not act improperly and could not have detected the fraud.
But, in June 2002, Andersen's US division was found guilty by federal prosecutors of obstructing the course of justice.
Pre-empting its official punishment, Andersen voluntarily agreed to stop auditing public companies in the US.
Many important clients had already deserted the sinking ships, and its international businesses has been divided up between its rivals.
Earlier attempts to save itself through a merger ended in failure.
Following the conviction, multi-million dollar lawsuits brought by Enron investors and shareholders demanding compensation are likely to follow, and could bankrupt the firm.
The company called the guilty verdict "wrong" and is contemplating an appeal.