During the 1940s, Gelbart began working as a writer at the age of sixteenfor Fanny Brice's radio show, and as a gag writer for Danny Thomas. After a brief stint in the army, where he wrote for Armed Forces Radio, Gelbart joined the writing staff of Duffy's Tavern, a popular radio program. He also wrote for Bob Hope, whom he followed to television. In the 1950s, he worked in television for Sid Caesar on Caesar's Hour, along with writers Neil Simon, Mel Brooks, Woody Allen, and Carl Reiner. Gelbart also wrote TV-movie Barbarians at the Gate.
Gelbart wrote the long-running Broadway musical farce A Funny Thing Happened on the Way to the Forum with Burt Shevelove and Stephen Sondheim. His Broadway credits include the musical City of Angels, which won him the Drama Desk Award for Outstanding Book of a Musical and an Edgar Award, and the Iran-contra satire Mastergate, as well as Sly Fox. In the early 1960s, he uttered the now-classic line, "If Hitler is alive, I hope he's out of town with a musical."
In 1962 and he collaborated with Shevelove on the screebnplay for The Wrong Box (1966), a British comedy film. Gelbart in 1982 co-wrote the Oscar-nominated screenplay for Tootsie. He also wrote the screenplays for Oh, God!, which starred George Burns, Blame It on Rio with Michael Caine and Demi Moore and the poorly-received 2000 film, Bedazzled with Elizabeth Hurley and Brendan Fraser.
In 1972, Gelbart was one of the main forces behind the creation of the television series M*A*S*H, writing and producing many episodes until leaving after the fourth season. As producer of M*A*S*H, Larry Gelbart provided numerous contributions to one of television's most innovative and socially aware sitcoms. But he has been a dynamic force in broadcasting for more than thirty years. Gelbart provided numerous innovations to an idea which had already made for a best-selling novel and box office hit. Recalling a Lenny Bruce bit on draft dodges, Gelbart created Corporal Klinger, a character who dressed in women's clothing in hopes of getting a "Section Eight" discharge. Written as a one-time character, Gelbart's Klinger, played by Jamie Farr, became central to the long-running series. When actor McLean Stevenson decided to leave the series, Gelbart was involved in the decision to "kill off" Stevenson's character, Colonel Henry Blake. This was the first time a series regular had met such a fate. Furthermore, Gelbart is credited with "The Interview" episode, an innovative script in which journalist Clete Roberts, playing himself, interviews the doctors of the M*A*S*H unit. Produced with a cold opening (no teaser, lead-in, or commercial), filmed in black and white, and shot in documentary style, it paved the way for the numerous innovations carried out by later M*A*S*H producers. After four seasons with M*A*S*H, Gelbart became worried he would grow repetitive and left the series.
Gelbart was a contributing blogger at The Huffington Post, and also was a regular participant on the alt.tv.mash newsgroup as "Elsig".
To Quote Mr. Gelbart:
“Today's audience knows more about what's on television than what's in life.”
“It was like electronic euthanasia.”
“Television is a weapon of mass distractrion.”
“If vaudeville had died, television was the box they put it in.”
“Most jokes state a bitter truth”
“One doesn't have a sense of humor. It has you.”
Goodnight Mr. Gelbart.