O'Byrne's remit will cover communications, government affairs and policy for Virgin Group, which brings together the brand's various ventures into airlines, holidays, gyms, banking, entertainment and philanthropy.
For the past three years she has been director of communications and public affairs for the London Legacy Development Corporation, the body tasked with reshaping the Olympic Park – now the Queen Elizabeth Olympic Park – in the wake of London 2012.
Her experience in policy and government communications includes work as special adviser to DCMS minister Tessa Jowell and a stint as head of communications for the Government Olympic Executive in the run-up to the Games.
She has also been director of communications at Ofsted, director of external affairs at the Institute for Public Policy Research and director of corporate communications for the Labour Party.
At Virgin Group it is understood her role will report to director of external relations Nick Fox and will have a reach across Europe and the Middle East.
One source with insight into the hire pointed to her mix of experience, which also includes working at BT, as key for the new role.
"She has a strong blend of corporate and consumer PR experience allied to her work in government, all of which should help her bring the Virgin story into sharper focus," they said.
Both Virgin Group and the London Legacy Development Corporation declined to comment.