The new “senior programme director” will be in charge of ensuring the hospital is finished without the safety issues identified in recent weeks which will cost the NHS at least £16 million to fix.
Mary Morgan, who is director of strategy, performance and service transformation at NHS National Services Scotland, will take up the role today and will report directly to the Scottish Government.
She said: “I recognise the importance and the challenge of the task ahead, whilst acknowledging the large amount of work that has been already undertaken.”
Last week, Ms Freeman announced the opening of the hospital would be delayed until autumn 2020, three years late, following the publication of an independent report into the failings surrounding the construction of the building.
She said: “I am pleased to have swiftly appointed Mary Morgan to the role of senior programme director. Mary comes with a wealth of experience within NHS Scotland, leading on major change programmes, and will bring extensive expertise and knowledge to this role.
“Our overriding priority is that the children and families who depend on these hospital services can receive them in the safest way possible. The current situation is not one anyone would choose – but it is one I am determined to resolve.”
The appointment comes amid reports of more than 70 people working at the new hospital every day without anything to do.
Taxpayers have also been paying £1.4m a month to a private consortium for the empty hospital since February.
Other failings have also been revealed with the contractors of the new hospital being accused of underbidding for the project by £11.6m when they won the job.
Integrated Health Solutions Lothian, a consortium led by Brookfield Multiplex, won the contract six years ago but a report by Audit Scotland showed NHS Lothian had paid the company an extra £11.6m to fix drainage, heater and fire detector issues.