Harold is first known as a writer in National Lampoon's Animal House. Harold directed National Lampoon's Vacation in 1983, starring Chevy Chase and Beverly D'Angelo. Harold's daughter Violet Ramis had a minor role in the movie. As Randy Quaid/Eddie Johnson's daughter in the movie Daisy Mable Johnson.
Harold is best known for his work on Meatballs, Caddyshack, Year One, Ghostbusters, Groundhog Day, and Stripes etc.
On February 24th, 2014, Mr. Ramis passed away due to complications from a rare disease Autoimmune inflammatory vasculitis, a condition he battled for four years. Ramis died Monday morning in his Chicago-area home and is survived by his wife, Erica Mann Ramis, three children and two grandchildren.
- For Ghostbusters, Harold Ramis decided Egon would never smile per a description of him in the script as a "New Age Mr. Spock."
- In The Real Ghostbusters episode "Take Two", Winston mentions Harold Ramis' last name while reading off the cast of the movie being made about the Ghostbusters.
- John Melchior took a flight to Chicago and spoke with Ramis about committing to Ghostbusters: The Video Game. Ramis was somewhat reluctant at first but once he was sure that it was not going be a cheaply made game, then Melchior went to see Aykroyd. 
- Melchior and the team went to the set of "The Office" and after some waiting, showed Ramis the demo of the game during a break from directing an episode.
- During a debate about the Museum of (Super)Natural History Level, John Melchior called up Harold Ramis for advice. At the time, Ramis was on the set of The Office directing an episode.
- On page 12 of Ghostbusters Volume 2 Issue #1, H. Ramis is listed as one of the authors of the technical report.
- In the Ghostbusters: Mass Hysteria hard cover collection, on page five, Ramis is referenced in Dan Aykroyd's introduction.
- In Ghostbusters: Get Real Issue #3, page 14, an eight pin board in the Proton Pack is named after Ramis.
- A bust of Harold Ramis makes a cameo in Ghostbusters (2016 Movie). Ramis' bust is outside of Erin Gilbert's office at Columbia University. When Dean Harold Filmore was about to leave then said, "Never mind." a second time, the bust is in view.
- The bust was given to Erica Ramis, Harold's wife. She in turn gave it to the Ramis Film School at The Second City in Chicago. It resides in the bar. 
- Harold Ramis' son Daniel Ramis has a cameo as the Metal Head who gives Rowan North a high five in Chapter 8 of the 2016 movie.
- On page 215 of Ghosts from Our Past: Both Literally and Figuratively: The Study of the Paranormal (Three Rivers Press), Harold Ramis is thanked in the acknowledgment section.
- Ramis is mentioned in the Introduction of Ghostbusters 101: Everyone Answers The Call TPB on page 2.
- On page 2 of Teenage Mutant Ninja Turtles/Ghostbusters Volume 2 Issue #3, one of the Ghostbusturtles has the first name of Harold Ramis.
- On Cover B of Ghostbusters Crossing Over Issue #4, the Harold Ramis bust from outside Dean Harold Filmore's office in the 2016 movie appears on the lower level.
- On page 1 of Ghostbusters Year One Issue #2, Bob Douglas mentions pledging to Delta Tau Chi. This was the name of the fraternity in "Animal House" which was co-written by the late Harold Ramis and directed by Ivan Reitman.
- On page 4 of Ghostbusters Year One #2, Peter's hairstyle is based on Bill Murray's character Tripper in "Meatballs" (1979) which was directed by Reitman and co-written by Ramis. Egon's hairstyle is based on Harold Ramis' character Russell in "Stripes" (1981) which was also directed by Reitman and co-written by Ramis.
- CNN 2/24/14
- Harold Ramis (1999). Ghostbusters- Commentary (1999) (DVD ts. 01:02:48-01:03:14). Columbia TriStar Home Video. Harold Ramis says: "Well, just for you acting buffs out there. I'd made a decision not to smile in this entire movie. That's about as close to a smile as I get. For you Spengler fans, he was described in the script as a New Age Mr. Spock. I tried to play him that way."
- Winston Zeddemore (2009). The Real Ghostbusters - "Take Two" (1986) (DVD ts. 06:20-06:24). Time Life Entertainment. Winston says: "Murray...Aykroyd...Ramis. What's that? A law firm?"
- Spook Central "Ghostbusters Fan Fest - Ghostbusters: The Video Game Panel" 6:05-6:15 10/4/19 Panelist says: "So the first thing I did was fly to Chicago, uh, to talk to Harold and convince him. Then he was somewhat reluctant to do it, uh, until we talked to Dan. And then he was interested enough for us to approach Dan."
- Spook Central "Ghostbusters Fan Fest - Ghostbusters: The Video Game Panel" 6:29-6:37 10/4/19 Panelist says: "And then we went to The Office, uh, the set of The Office where Harold was directing an episode and we sat in the waiting room of The Office and we showed him the demo."
- Playstation Blog "Inside the Development of Ghostbusters: The Video Game" 10/2/19 John Melchior says: "One time, there was a debate about the museum location. I called Harold, who was on the set of The Office directing an episode, and he called me back from his break to weigh in and provide guidance about what would best fit the world. Dan was also always there. He would regularly see the game and review the levels we were creating to see how they played into the canon of their creation."
- Ray Stantz (2015). IDW Comics- "Ghostbusters: Get Real Issue #3" (2015) (Comic p.14). Ray says: "It was a snap once we upgraded the Ramis Boards from a six-pin to an eight!"
- paulfeig Tweet 11/27/16
- paulfeig Tweet 10/3/16 Paul Feig says: "He's the one who high fives Rowan outside the concert & says "Ozzy rocks!" That's Harold's son Daniel."