Sarah Munby, a director general in the Department for Business, Energy and Industrial Strategy, has been named its permanent secretary.
Munby, who takes up her new role today, has been director general for business sectors since last July.
At 38, she is understood to be the youngest perm sec in Whitehall.
Before joining BEIS last year she spent 15 years at McKinsey, where she was a partner and led the management consultancy’s UK and Ireland strategy and corporate finance practice.
BEIS said in a statement that Munby had “worked with some of the UK’s largest companies to change their strategic direction, and led much of McKinsey’s work on productivity across the UK economy”.
The appointment comes three months after the department signed a deal to pay executive search company Russell Reynolds Associates up to £63,000 to fill the post.
Munby succeeds Alex Chisholm, who was promoted to civil service chief operating officer in April. Sam Beckett has been acting perm sec since then, and will provide support to ensure a “smooth transition”, BEIS said.
Cabinet secretary Sir Mark Sedwill said Munby had been “instrumental in supporting businesses to help them prepare for exiting the EU and in responding to Covid-19, and brings with her a wealth of experience from her time as a partner at McKinsey”.
Sedwill added that Beckett had provided “exceptionally strong leadership” to the department since Chisholm’s departure.
Business secretary Alok Sharma said the appointment was “very good news for the department and for this government”.
“Sarah is an outstanding public servant who has already made a significant contribution to the work of the department,” he said.