Martyn Thomas has left the Rugby Football Union with immediate effect after the threat of a misconduct charge was lifted.
Thomas, who was due to leave Twickenham on December 16, has been replaced in the role of acting chief executive by Stephen Brown, the RFU's chief financial officer.
The news of Thomas' departure came less than an hour after Charles Flint QC had announced there was no evidence to bring disciplinary action against him.
Thomas was criticised in the Blackett Report for his role in the hiring and firing of John Steele as chief executive.
Judge Jeff Blackett, the RFU's chief disciplinary officer, indicated on September 2, during the debate on a vote of no confidence in Thomas, that he had sufficient evidence on which to bring disciplinary charges.
RFU president Willie Wildash subsequently engaged Flint to determine whether any charges should be brought. Wildash announced on Tuesday: "I have now received Charles Flint's opinion. In it he states that there is no basis, on the evidence he has seen, for bringing disciplinary proceedings against any member of the Council."
On December 16 Thomas will relinquish the chairmanship of England Rugby 2015 , the directorship of European Rugby Cup Ltd and step down from the International Rugby Board Council and the Six Nations Committee. But he has decided to hand over the RFU reins to Brown immediately.
He said: "Stephen has increasingly taken over the day-to-day running of the RFU since I announced on November 2 that I would not be renewing my contract after December 16. He has demonstrated in the time that he has been at the RFU that he is immensely capable and this has been underlined once again in the last few weeks.
"It is therefore entirely logical that he takes on the role of acting CEO as soon as possible. He is highly respected by the staff and I have every confidence that he will provide the stability and leadership needed until a new permanent CEO takes office.
"It has been an honour to serve the union, most recently as acting CEO where I have been lucky enough to get to know the staff who continue to work so hard for the good of the game. They are led by a superb Executive. The RFU has much to look forward to, not least hosting the Rugby World Cup in 2015, and I wish them well."