Willis, a former channel director of programs and CEO of United Prods., will join the BBC’s executive committee in June, reporting to director general Greg Dyke.
The factual and learning arm, which has a commercial relationship with Discovery, has a budget of £300 million ($468 million).
The position had been shared by two execs, Michael Stevenson, who resigned in January, and Glenwyn Benson, recently appointed controller of factual TV.
“I have enjoyed a remarkable time working with WGBH at the heart of American public broadcasting,” Willis said. “However, the chance to join the BBC and lead one of its major production divisions is enticing. It has a worldwide reputation and I’m looking forward to joining Greg and the executive committee soon.”