Former Cambridge United chairman Paul Barry has become the club's new owner, while Jez George has resigned from his role as chief executive.
Barry, based in the United States but brought up in Cambridge, has been an investor for 18 years and the club's largest shareholder since 2008.
He was replaced as U's chairman by Dave Doggett after stepping down in 2013.
In a statement, the Seattle businessman reaffirmed the club's plans to build a new ground on their Abbey Stadium site.
Cambridge directors Shaun Grady, Steve Chamberlain and ex-player Graham Daniels, who had been overseeing the League Two club on an interim basis since Doggett's resignation in December, will remain on the executive board.
"A new stadium has to be at the heart of our future ambitions. The Abbey is the club's home and a stadium full of so many special memories, but we need to modernise and improve it if we are to progress in the way we all want," Barry said.
"I will be putting new investment into the club but it is important to manage expectations. This does not mean a sudden windfall to the playing budget."
George, who has also been manager and director of football during his 12 years at the club, will retain an advisory role.
Barry added: "He has made a huge contribution. It is no exaggeration to say he has done everything literally apart from pulling on the shirt."