The BBC's head of finance, Anne Bulford, has become the corporation's first female deputy director general as part of a management restructure.
Bulford will become the first person in the role since the departure of Mark Byford in 2011.
She will also take on responsibilities for marketing and commercial rights.
Director general Tony Hall said the restructure would create "a simpler BBC with fewer layers and clear lines of accountability".
It will also see the creation of a new Nations and Regions department covering output from outside London, headed by a controller who will sit on the corporation's executive board in place of the directors of Scotland, Wales and Northern Ireland.
Other changes include Charlotte Moore becoming director of content alongside her current role as controller of BBC One, and James Purnell becoming director of strategy and education, overseeing Children's and Learning.
'Clear leadership and focus'
Lord Hall said the changes would "help ensure that the BBC is best equipped" to "engage with our audiences as we enter our centenary year".
"We must never stand still. We must always be looking to innovate and change. The new executive [team] will lead this process of creative renewal to ensure the BBC remains the most creative force in the world."
He added the restructure was "reflecting priorities at the top of the organisation to give clear leadership and focus on the things that matter most".
Lord Hall also said the creation of the nations and regions department was important because the UK was "changing and changing fast [and] the BBC needs to recognise and address that".
"It will be a challenge in an environment where resources are tight, but it is a priority and the steps taken today recognise that."