After being discovered by an agent at the opening of his older brother Matt's 1982 film Tex, Dillon landed a succession of high-profile supporting film roles, usually playing out-of-control teens (a prankster in Heaven Help Us, a trigger-happy soldier in Platoon). In the '90s the prolific actor appeared in numerous films, although their quality could be easily determined by his billing: If he was the star (Misbegotten, Hidden Agenda), it was a B-movie. As the decade wore on, he turned his attention to TV, with recurring roles on NYPD Blue and 24. Then, in a classic case of art imitating life, Dillon signed on to Entourage as the less-famous brother of an up-and-coming Hollywood star. At once pompous, egocentric and completely insecure, Dillon's hilarious characterization revitalized his career, earning him Emmy nominations, and often stole the show.
- Discovered by an agent at the opening of brother Matt Dillon's 1982 film Tex.
- Tutored by session drummer Allan Schwartzberg for his role as drummer John Densmore in 1991's The Doors.
- Studied for his role as the gung-ho Bunny in 1986's Oscar-winning Platoon by reading Run Through the Raindrops, a novel by technical advisor and retired Marine captain Dale Dye.
- Read for the NYPD Blue role of Danny Sorenson, which went to Rick Schroder, before landing a recurring role as Officer Neil Baker.
- An avid golfer himself, his father Paul is golf coach at Fordham University and an artist whose portraits of Bobby Jones, Arnold Palmer and others hang in the famed Winged Foot Golf Club in Mamaroneck, NY.
- 2008, Emmy — Outstanding Supporting Actor in a Comedy Series: Nominee
- 2006, Screen Actors Guild Awards — Outstanding Performance by an Ensemble in a Comedy Series: Nominee
- 2007, Screen Actors Guild Awards — Outstanding Performance by an Ensemble in a Comedy Series: Nominee
- 2008, Screen Actors Guild Awards — Outstanding Performance by an Ensemble in a Comedy Series: Nominee
- 2007, Emmy — Outstanding Supporting Actor in a Comedy Series: Nominee
- 2008, Golden Globe — Best Performance by an Actor in a Supporting Role in a Series, Miniseries or Motion Picture Made for Television: Nominee
- 2009, Emmy — Outstanding Supporting Actor in a Comedy Series: Nominee
- Brian Dillon — Brother
- Ava Dillon — Daughter
- Jane Stuart — Wife
- Tim Dillon — Brother
- Mary Ellen Dillon — Mother
- Paul Dillon — Father
- Kate Scholz — Sister
- Matt Dillon — Brother
- Paul Dillon Jr. — Brother
- Attended School of Visual Arts, New York, New York, United States