[26] In 2022, for the BFI Sight and Sound "Greatest Films of All Time" poll, Hertzfeldt listed the following ten films as important titles that had "knocked me over the head at some point in life and continue to do so": The Act of Killing, Citizen Kane, Close Encounters of the Third Kind, Gates of Heaven, The Godfather, Goodfellas, Harold and Maude, Monty Python's Life of Brian, The Pianist, and 2001: A Space Odyssey.

Hertzfeldt initially used antique 16 mm or 35 mm–film cameras to photograph his drawings and often employs old-fashioned special effect techniques such as multiple exposures, in-camera mattes, and experimental photography.

While some of these techniques are as established as an occasional stop-motion animation sequence or a universe of moving stars created by back-lit pin holes, other effects are innovations on classical methods, as seen with the in-camera compositing of multiple, split-screen windows of action in It's Such a Beautiful Day.

[31] Built in the late 1940s, it was one of the last remaining functioning cameras of its kind left in the world, and Hertzfeldt found it to be a crucial element in the creation of his films and their visuals.

You could make a cartoon in crayons about a red square that falls in unrequited love with a blue circle, and there wouldn't be a dry eye in the house if you know how to tell a story.

[33]It's not unusual for Hertzfeldt to write, direct, produce, animate, photograph, edit, perform voices, record and mix sound, and/or compose music for one of his films, at times requiring years to complete a single short by working alone.

[34]In another Reddit "AMA", on the subject of creativity, Hertzfeldt suggested the following: ...You need to try to return to the time when you were a little kid, creating things on a big sheet of paper in a beautiful sunbeam, and not having any cares at all about how it might one day be received.

Its partially improvised vocal performances helped the short win twenty-five awards, including the Grand Prize at the New Orleans Film Festival.

In appearances, Hertzfeldt has told the humorous story of how he was tempted to produce the worst possible cartoons he could come up with for the companies, run off with their money, and see if they would make it to air.

From a commercial standpoint I guess I've made some pretty inscrutable decisions, like following up Rejected with a sprawling abstract film about human evolution, but it's really just been whichever ideas won't go away at the time.

[51] Everything will be OK is the first chapter of a three-part story about a man named Bill whose daily routines, perceptions, and dreams are illustrated onscreen through multiple split-screen windows.

Bill's seemingly mundane life, narrated in humorous and dramatic anecdotes, gradually grows dark as we learn he may be suffering from a possibly fatal neurological disorder.

Animated still photographs are also incorporated inside certain windows, as well as a handful of the colorful special effects and experimental film techniques that Hertzfeldt first utilized in The Meaning of Life.

It was the longest opening gag in the show's history and was described by Spin Magazine as "mind-melting," and "two of the strangest minutes of television ever to air on a major network during prime time.

"[64][65][66] The sequence depicts Homer accidentally using a time-traveling remote control that regresses him to his original 1987 character model, then propels him into a distant future incarnation of the show called The Sampsans where he and his family have evolved into grotesque, mindless, catchphrase-spouting creatures.

Illustrator Julia Pott performs the voice of the short's lead character, opposite Hertzfeldt's then-four-year-old niece, who was recorded while drawing and playing.

"[68] Critics were universally positive in their reviews, describing the science fiction film as "one of the most satisfying shorts since Chris Marker's landmark 1962 La Jetee and almost certain to be the highlight of this year's Sundance, full stop,"[69] "dazzling, enthralling"[70] and "astonishing.

"[75] World of Tomorrow Episode Two premiered in 2017 at Fantastic Fest in Austin and received rare "A+" reviews from Indiewire and Collider, where it was described as "another soulful sci-fi masterpiece.

[86] Sight and Sound Magazine compared ME to the "broken-puzzle poetry of David Lynch's Mulholland Drive", describing it as a "socio-cosmic satire" about "communication breakdown and its upshots -- solipsism, abandonment, blight, fascism -- set in a contemporary landscape of high tech and low morality... the film is [Hertzfeldt's] most coded, gnomic, and perhaps intuitive; both on the nose and deeply cryptic.

"[88] Indiewire called ME a "brilliant apocalyptic musical about narcissism," noting it "seems to explode from a cosmic collision between nothing and everything all at once... these films keep stretching toward the stars as they probe deeper into the pit of our souls.

[106] In 2007, Everything Will Be OK advanced to the "shortlist", the final round of voting as a contender for an Academy Award nomination for Best Animated Short Film, but did not make the ultimate list of five nominees.

[107] In 2007, Hertzfeldt accepted an invitation from the George Eastman House's motion picture archives to indefinitely store and preserve the original film elements and camera negatives of his collected work.

In December 2015, Hertzfeldt received a special award from the Austin Film Critics Association, "in celebration of a career of remarkable short filmmaking and contributions to animation spanning two decades, with 2015's award-winning World of Tomorrow being recognized as his best work to date."

The special features for Don Hertzfeldt Volume One: 1995–2005 included a time-lapse documentary of the making of The Meaning of Life called "Watching Grass Grow", The Animation Show Trilogy cartoons, Lily and Jim deleted dialogues and outtakes, Rejected trivia captions, The Meaning of Life special effects audio commentary, an over 140-page "archive" section (of rare footage from Hertzfeldt's earliest cartoons, original pencil tests, deleted sequences, abandoned footage, and sketch to scene comparisons), Lily and Jim audio commentary, Rejected audio commentary, and a retrospective booklet, with liner notes by Hertzfeldt.

Special features for the release included over 40 minutes of live Q&A material from the touring program, the cartoon Wisdom Teeth, a deleted scene from It's Such a Beautiful Day, and a 24-page booklet.

In 2015, Hertzfeldt ran a Kickstarter campaign to fund future productions, with the Blu-ray debut of It's Such a Beautiful Day and World of Tomorrow as the central pledge reward.

In a 2015 Vanity Fair interview, Hertzfeldt said: ...Many people in our industry would see advertising work as the ultimate goal, which really illustrates the sad state of affairs that's set up for many young animators.

The most well-known instance of this is a series of television ads for Kellogg's Pop-Tarts, which use black and white stick figures, "squiggly" animation, surreal humor, and even an occasional crumpling paper effect, all very similar to Hertzfeldt's style.

[120] In Canada, the not-for-profit corporation Encorp has used a Hertzfeldt-like style of short animation clips on TV and the Internet to promote its "Don't Mess With Karma" campaign to encourage recycling.

[121] One of the latest ad campaigns to use an art style similar to Hertzfeldt's is Krystal fast food restaurant to promote their Blitz Energy Drink.