Simon Roberts has been appointed as the interim team principal for Williams.
Roberts spent 17 years at McLaren before joining Williams as managing director in May.
He will head up the British team's Formula One operation after its founder Sir Frank Williams, and deputy team principal Claire Williams, left the sport following the sale to US investment firm Dorilton Capital.
Sir Frank had been the team principal. His daughter Claire assumed the day-to-day running of the team in 2013. The Italian Grand Prix on Sunday marked the family's 739th and concluding race in F1.
Roberts said: "I am delighted to be announced as acting team principal for Williams during this transitional period.
"It is an exciting time ahead for the team, a new era for Williams and one that I am excited to be playing a part in.
"I look forward to the challenge ahead as we look to take the team back to the front of the grid."
Williams are the third most successful constructor in the sport's history, behind only Ferrari and McLaren. They have won 114 times and 16 combined drivers' and teams' titles.
Despite their great success in the 1980s and 1990s – producing Nelson Piquet, Nigel Mansell and Damon Hill as world champions – Williams have won just one race in the last 16 years.
They have finished bottom of the constructors' championship for the past two seasons and are without a point in 2020. Despite the sale, they will continue to be called Williams and operate out of its Grove headquarters in Oxfordshire.
Prince William's brother-in-law, James Matthews, is on the company's new-look board of directors. Chairman of Dorilton Capital, Matthew Savage, and Darren Fultz, the firm's co-founder and CEO, will also sit on the board.
It is understood they will now work on a shortlist in order to have a team principal in position for the 2021 campaign.
Earlier on Tuesday, Williams chief executive officer Mike O'Driscoll announced he will step down from his role later this year.
"It has been and remains a huge privilege to be part of this great team," said O'Driscoll, 64.
"I am proud to have played my part in securing the long-term future of Williams and look forward to working closely with Matthew and his team, to ensure a smooth transition and the best possible trajectory for future success."