[1] He graduated from Ithaca College, and earned a master's degree in communication arts from William Paterson University in 1972.
In 1989, he independently produced and directed the film The Feud, based on the 1983 novel by Thomas Berger.
The film attracted the attention of Steven Bochco, who hired D'Elia to direct an episode of Doogie Howser, M.D.. D'Elia went on to direct episodes of numerous other television series including Northern Exposure, Glee, Chicago Hope, Ally McBeal, The Practice, Boston Legal, and The West Wing.
D'Elia was an executive producer and a director of Chicago Hope, Boston Legal, Ally McBeal, Harry's Law, Monday Mornings, The Crazy Ones (all collaborations with David E. Kelley), and the Shonda Rhimes series How To Get Away With Murder.
an executive producer and a director for the Disney+ series Big Shot starring John Stamos.