Ramis was the original head writer of the television series SCTV, on which he also performed, as well as a co-writer of Groundhog Day and National Lampoon's Animal House (1978).

[1] Filmmakers and actors including Jay Roach, Jake Kasdan, Adam Sandler, Judd Apatow, and Peter and Bobby Farrelly have listed his films among their favorites.

[11]Ramis began writing parodic plays in college, saying years later, "In my heart, I felt I was a combination of Groucho and Harpo Marx, of Groucho using his wit as a weapon against the upper classes, and of Harpo's antic charm and the fact that he was oddly sexy—he grabs women, pulls their skirts off, and gets away with it.

[13] Following his work in St. Louis, Ramis returned to Chicago, where by 1968, he was a substitute teacher at schools serving the inner-city Robert Taylor Homes public housing development.

[14] He also became associated with the guerrilla television collective TVTV, headed by his college friend Michael Shamberg, and wrote freelance for the Chicago Daily News.

I wrote a spec piece and submitted it to the Chicago Daily News, the Arts & Leisure section, and they started giving me assignments [for] entertainment features.

[18] Later, Ramis became a performer on, and head writer of, the Canadian sketch-comedy television series SCTV during its first three years (1976–1979).

[17] Characterizations by Ramis on SCTV include weaselly, corrupt and constantly sweating Dialing for Dollars host/SCTV station manager Maurice "Moe" Green, outwardly amiable (but thoroughly fascist) cop Officer Friendly, exercise guru Swami Bananananda (whose real name was Dennis Peterson), stern board chairman Allan "Crazy Legs" Hirschman and home dentist Mort Finkel.

Ramis got involved after the mysterious death of his friend Peter Ivers, who had hosted Jove's underground show New Wave Theatre.

In 1982, Ramis was attached to direct the film adaptation of the Pulitzer Prize-winning book A Confederacy of Dunces by John Kennedy Toole.

[20] In 1984, Ramis collaborated with Dan Aykroyd on the screenplay for Ghostbusters, which became one of the biggest comedy hits of all time, in which he also starred as Dr. Egon Spengler.

Ramis frequently depicted the qualities of "anger, curiosity, laziness, and woolly idealism" in "a hyper-articulate voice".

[1] Ramis also occasionally acted in supporting roles in acclaimed films that he did not write or direct, such as James L. Brooks's Academy Award-winning As Good as It Gets (1997) and Judd Apatow's hit comedy Knocked Up (2007).

[22] In 2004, Ramis turned down the opportunity to direct the Bernie Mac-Ashton Kutcher film Guess Who, then under the working title "The Dinner Party", because he considered it poorly written.

Ramis spent six weeks trying to get the film greenlit because he had difficulty reaching an agreement about stars John Cusack's and Billy Bob Thornton's salaries.

[25] A reboot to the franchise, also called Ghostbusters, was eventually made and released in 2016, directed and co-written by Paul Feig.

On July 2, 1967,[3] he married San Francisco artist Anne Plotkin, with whom he had a daughter, Violet Ramis Stiel.

[3] Although Ramis maintained humanist beliefs, Erica's Buddhist upbringing greatly influenced his philosophies for the rest of his life, and he became friends with the Dalai Lama.

[29][30] His pastimes included fencing, ritual drumming, acoustic guitar, and making hats from felted fleece; additionally, he taught himself to ski by watching skiers on television.

[1] In May 2010, Ramis contracted an infection that resulted in complications from autoimmune inflammatory vasculitis and lost the ability to walk.

[31] A private funeral was held for him two days later with family, friends, and several collaborators in attendance, including Dan Aykroyd, Chevy Chase, Eugene Levy, Dave Thomas, David Pasquesi, Andrew Alexander, and the widows of John Belushi and Bernard Sahlins.

[32] Upon Ramis' death, then-President Barack Obama released a statement, saying, "When we watched his movies—from Animal House and Caddyshack to Ghostbusters and Groundhog Day—we didn't just laugh until it hurt.

At that point, Ramis had lost most of his ability to speak, so Murray did most of the talking over several hours, as the two finally made peace.

Colbert said that "as a young, bookish man with glasses looking for a role model, I might have picked Harold Ramis."

[43][44] In the 2021 movie Ghostbusters: Afterlife, the age-progressed image of Ramis appears as the ghost of Egon Spengler; a dedication before the end credits also reads "for Harold."