Her whole family all worked behind the camera, and Stewart thought she would become a writer/director, but never considered being an actor. "I never wanted to be the center of attention – I wasn't that 'I want to be famous, I want to be an actor' kid. I never sought out acting, but I always practiced my autograph because I love pens. I'd write my name on everything." Stewart's acting career began at the age of eight, after an agent saw her perform in her elementary school's Christmas play. After a year of auditioning, Stewart's first role was a nonspeaking part in the film The Thirteenth Year. Then, she had another part in the film The Flintstones in Viva Rock Vegas as the "ring toss girl". She subsequently appeared in the independent film The Safety of Objects, in which she played the tomboy daughter of a troubled single mother (Patricia Clarkson). Stewart had a major role in the Hollywood film Panic Room, playing the diabetic daughter of a divorced mother (Jodie Foster). The film received generally positive reviews, and Stewart garnered positive notices for her performance. Kristen Stewart was nominated for a Young Artist Award for her performance.
After Panic Room's success, Stewart was cast in another thriller, Cold Creek Manor, playing the daughter of Dennis Quaid's and Sharon Stone's characters. She was again nominated for a Young Artist Award for her performance. It was revealed that at about this time in her career, she had to be homeschooled due to her irregular schedule, which was affecting her grades. She said, "I started homeschooling because my teachers were failing me. I think it was just resentment – I made more work for them. But homeschooling is great; you can study what you want, which allows you to get more excited about what you're doing".
Her first starring role followed, in the children's action-comedy Catch That Kid, opposite Max Thieriot and Corbin Bleu. Stewart also played the role of Lila in the thriller Undertow. To date, Stewart's most critically acclaimed role may be in the Showtime television film Speak (2004), based on the novel by Laurie Halse Anderson. Stewart, 13 at the time of filming, played high school freshman Melinda Sordino, who stops almost all verbal contact after being raped. Kristen Stewart received great praise for playing the character, who had only a few speaking lines, but kept up a darkly humorous commentary inside her head throughout the film.
In 2005, Stewart appeared in the fantasy-adventure film Zathura, playing the role of Lisa, the irresponsible older sister of two little boys, who turn their house into a spacecraft hurtling uncontrollably in outer space by playing a board game. The film received praise by critics, but Stewart's performance did not garner much media attention, as it was noted that her character is immobilized during most of the film. The following year, she played the character Maya in Fierce People, directed by Griffin Dunne. After that film, she received the lead role of Jess Solomon in the supernatural thriller film The Messengers.
On November 16, 2007, Summit Entertainment announced that Kristen Stewart would play Isabella "Bella" Swan in the film Twilight, based on Stephenie Meyer's bestselling vampire romance novel of the same name. Stewart was on the set of Adventureland when director Catherine Hardwicke visited her for an informal screen test which "captivated" the director. She stars alongside Robert Pattinson, who plays Edward Cullen, her character's vampire boyfriend. The film began production in February 2008 and finished filming in May 2008. Twilight was released domestically on November 21, 2008. Her performance garnered mixed reviews with some critcs calling her "the ideal casting choice" and praising her for conveying "Bella's detachment, as well as her need to bust through it" while others criticized her acting for being "wooden" and lacking variety in her facial expressions which they described as "blank". After the release of Twilight, Kristen Stewart was awarded the MTV Movie Award for Best Female Performance for her portrayal as Bella Swan.
Kristen Stewart reappeared as Bella in the sequel, The Twilight Saga: New Moon to critical acclaim, receiving much more positive reviews than her portrayal of the same character in Twilight. Jordan Mintzer from Variety called Stewart "the heart and soul of the film" and praised her for giving "both weight and depth to dialogue...that would sound like typical chick-lit blather in the mouth of a less engaging actress, and she makes Bella's psychological wounds seem like the real deal" while critics who gave the film its worst reviews still found her performance "bringing plenty of soul" to the character. She reprised this role in The Twilight Saga: Eclipse.
Kristen Stewart has been nominated and presented with the BAFTA Rising Star award. At the 2010 82nd Annual Academy Awards, Stewart and Twilight co-star Taylor Lautner presented a tribute in honour of the horror movie genre.
In 2009, Kristen Stewart starred in The Yellow Handkerchief, which debuted at the Sundance Film Festival and was released into theaters in 2010 by Samuel Goldwyn Films. She also starred alongside James Gandolfini in Welcome to the Rileys, which premiered at the Sundance Film Festival in January 2010.
Stewart most recently portrayed rock star Joan Jett in The Runaways, a biopic of the titular band from writer-director Floria Sigismondi. Stewart met with Jett over the 2008–2009 New Year to prepare for the role, and ended up prerecording songs in a studio for the film. She received nearly unanimous praise for her performance. Josh Tyler of Cinema Blend pronounced her to be "a modern day James Dean. She gives the kind of performance in The Runaways that hasn’t been seen on screen since his death. The Runaways is her Rebel Without a Cause ... she’s absolutely brilliant as Joan Jett." The Metro Times wrote, "It turns out that Stewart is actually really good at capturing Jett's icy, tough-but-cool girl swagger, adding the needed touches of vulnerability that transform it into a pretty terrific performance... Stewart is a genuine rock star here." Also, A. O. Scott of The New York Times noted "Ms. Stewart, watchful and unassuming, gives the movie its spine and soul."
Kristen Stewart was listed as the highest earning female actress in Hollywood in the "2010's Top Hollywood Top Earners List" compiled by Vanity Fair. Throughout 2010, Stewart earned an estimated $28.5 million for all her movie appearances.
The Twilight Saga: Breaking Dawn- Part 1 was released on November 18, 2011. The film was successful in the box office making $283.5 million its opening weekend. Though the film received negative reviews, Stewart's perfomance was mostly praised. Gabriel Chong said that Stewart's performance, calling it "mesmerising" and saying that she "makes [Bella's] every emotion keenly felt that runs the gamut from joy, trepidation, anxiety, distress and above all quiet and resolute determination" and the Village Voice's Dan Konis saying Stewart "beautifully underplays" the role. However, some critics found that despite Pattinson and Stewart's chemistry, the relationship came off like a "charade" or that none of the three leads were convincing in their roles.
In March 2011, it was confirmed that Kristen Stewart will playing the leading role in the film Snow White and the Huntsman. Filming began on August 15 and is set to be released on June 1, 2012.
Stewart has also been attached to an upcoming big-budget, live-action adaptation of Akira from Warner Brothers for the role of Ky. On December 6, 2011, Stewart was named number one on Forbes magazine's list of Hollywood's Best Actors for the Buck.