Birkitt's career at CBS started before she graduated from college, when she worked as an intern for "CBS News", "48 Hours", and the "Late Show" in early 1996. After graduation she became a member of the CBS page program and worked briefly as an associate producer at "48 Hours" on segments for correspondent Erin Moriarty. Deciding she was not "much of a news hound", she applied for a job as an office worker for David Letterman, helping to handle his charities and his Indy car racing team.