A former minister ousted in the General Election had been appointed as Theresa May's new Downing Street chief of staff.
Gavin Barwell, who lost his Croydon Central seat in the snap election called by Mrs May, will bring "considerable experience" to the post, the Prime Minister said.
His appointment comes following the resignation of Mrs May's closest aides Nick Timothy and Fiona Hill, who had served as joint chiefs of staff.
Mrs May said: "I'm delighted that Gavin Barwell accepted the role as my chief of staff.
"He has been a first class minister and is widely respected.
"He will bring considerable experience of the party to the post.
"As I said yesterday, I want to reflect on the election and why it did not deliver the result I hoped for.
"Gavin will have an important role to play in that.
"I look forward to working with him."
Former housing minister Mr Barwell said: "I voted for Theresa May to become Prime Minister.
"I believe she is the best person to heal the divisions in our country that last year's referendum and the General Election have laid bare, getting the best Brexit deal for the whole country and leading us towards a brighter future outside the EU.
"I'm thrilled to have the opportunity to serve as her chief of staff."