Bill Slater
From Tardis Wiki, the free Doctor Who reference
Bill Slater became head of serials at the British Broadcasting Corporation slightly before Tom Baker was cast as the fourth Doctor. Since Slater had previously directed Baker in a Play of the Month called The Millionairess, Baker famously wrote to Slater looking for work at around the time Barry Letts was casting Jon Pertwee's replacement. The letter worked, as Slater then placed Baker's name before Letts.[1][2]
He was also responsible for giving Philip Hinchcliffe the producership of Doctor Who.