Penn made his feature film debut in the drama Taps (1981), before taking roles in Fast Times at Ridgemont High (1982), Bad Boys (1983), and At Close Range (1986).

[20] The following year, Penn made his directorial debut with The Indian Runner (1991), a crime drama film based on Bruce Springsteen's song "Highway Patrolman", from the 1982 album Nebraska.

[15] Janet Maslin of The New York Times wrote, "Flirting constantly with the dangers of pure self-indulgence, Mr. Penn still manages to keep the improvisatory quality of this painful family drama from becoming overwhelming.

[25] Janet Maslin of The New York Times wrote, "Penn is a slugger of a film maker, whether pummeling his audience with the obvious or hammering home the heartfelt and true.

His second feature...has the same brute force that made his Indian Runner such a gripping oddity, bearing the distinctive stamp of Mr. Penn's raw, searching style".

[26] That same year he acting alongside Susan Sarandon starring in the Tim Robbins directed crime drama playing a racist murderer on death row in Dead Man Walking (1995).

Lisa Schwarzbaum of Entertainment Weekly compared the film to the works of John Cassavetes and wrote that Penn's performance "is so full of heart and talent".

[35] That same year he had a leading role in the Terrence Malick epic about the World War II battle for Guadalcanal in The Thin Red Line (1998) based on the 1962 novel of the same name by James Jones.

[39] In 2000, Penn acted in Julian Schnabel's drama Before Night Falls opposite Javier Bardem and Kathryn Bigelow's thriller The Weight of Water with Elizabeth Hurley.

[40][41] The following year he guest starred on the NBC sitcom Friends portraying Eric, a man who was engaged to Phoebe Buffay's sister Ursula, both of whom are played by Lisa Kudrow.

[46][47] That same year he acted in Alejandro González Iñárritu's psychological thriller 21 Grams opposite Naomi Watts and Benicio del Toro.

Jasmine Trinca, Idris Elba, Ray Winstone, Mark Rylance, and fellow Oscar-winner Javier Bardem appear in supporting roles.

His physical transformation and high-intensity confrontations...are showy, but the slowly unfolding role also lets him play quiet moments, and even light ones" adding, "It’s funny that I’m always surprised by how game Penn is to be a goofball.

[74] Ben Travers of IndieWire wrote of his performance, "Penn manages to bring life to his makeup-constructed character" adding "Even his manner of speech, spitting curse words while clenching his wooden pipe, befits the boil of a man that John Mitchell becomes".

Film critic Todd McCarthy of Deadline Hollywood wrote, "Sean Penn is at his absolute best here in a tremendously engaging performance as a salty working-class guy with an endless supply of opinions and ways of drawing out his passengers".

[84] The two starred in the panned Shanghai Surprise (1986), directed by Jim Goddard, and Madonna dedicated her third studio album True Blue (1986) to Penn, referring to him in the liner notes as "the coolest guy in the universe".

[87] In January 1989, Madonna filed for divorce again and reportedly withdrew an assault complaint against Penn following an incident at their Malibu, California, home during the New Year weekend.

[citation needed] On June 10, 2005, Penn visited Iran, where, acting as a journalist on an assignment for the San Francisco Chronicle, he attended a Friday prayer at Tehran University.

[124] On January 7, 2006, Penn was a special guest at the Progressive Democrats of America, where he was joined by author and media critic Norman Solomon and activist Cindy Sheehan at their "Out of Iraq Forum" in Sacramento, California, organized to support and promote the anti-Iraq War movement.

[129] On October 18, 2002, Penn placed a $56,000 advertisement in The Washington Post, publicly asking then President George W. Bush to end military hostilities in Iraq and elsewhere.

[143] On January 31, 2012, due largely to his visibility as an on-the-ground advocate for rescue and aid efforts in the aftermath, Penn was designated by then Haitian president Michel Martelly as Ambassador-at-Large for Haiti, the first time a non-Haitian citizen has held the position in the country's history.

"[146] In 2022, Penn expressed his position on masculinity, saying, "I am in the club that believes that men in American culture have become wildly feminised...I don't think that [in order] to be fair to women, we should become them."

He later told The Independent that "I think that men have, in my view, become quite feminised...There are a lot of, I think, cowardly genes that lead to people surrendering their jeans and putting on a skirt.

On March 23, 2012, accompanied by U.S. Consul General William J. Martin, Penn visited flood-stricken villages in Karim Bux Jamali, Dargah Shah Gurio, and Peero Lashari in the Badin District, where he distributed blankets, quilts, kitchen items, and other goods to flood survivors.

[154] In February 2012, during the Syrian civil war, Penn stood beside Venezuelan president Hugo Chávez as Venezuela supported the government of Syria, led by Bashar al-Assad.

"[160] Penn's friendship with Chávez and his praise for Cuban dictator Raúl Castro have been criticized by human rights activist Thor Halvorssen and media, including The New York Times, the Los Angeles Times, The New Criterion, and The Advocate, each of which alleged that Castro and Chávez's strong anti-LGBT stances clashed with Penn's support for LGBT groups.

"[181][182][183] The comments were taken as support of Argentina's claim to the islands and evoked reactions in British media, including a satirical article in The Daily Telegraph requesting that Penn "return his Malibu estate to the Mexicans".

[186] Lauren Collins wrote in The New Yorker, "As of today, Sean Penn is the new Karl Lagerfeld—the man upon whom, having disrespected something dear to the United Kingdom, the British papers most gleefully pile contempt".

[187] Penn later claimed said his comments were misrepresented in British press and that his criticism of "colonialism" was a reference to the deployment of Prince William as an air-sea rescue pilot, describing it as a "message of pre-emptive intimidation".

He claimed that the Prince's posting meant "the automatic deployment of warships", and stated: "My oh my, aren't people sensitive to the word 'colonialism', particularly those who implement colonialism.