Born Julie Anne Smith on 3 December 1960, at the Fort Bragg army installation in North Carolina, Julianne Moore had to spend her early years moving around the United States due to the transferable occupation of her father, who was a military judge. Her Scottish mother, Anne, who immigrated to the States in 1951, was a  psychiatric social worker. At the age of sixteen, when Julianne was attending Justice High School in Virginia, the family moved to Frankfurt, Germany and she was admitted to Frankfurt American High School. Although the constant relocating made her an insecure child and she had to struggle to establish friendships, she was a very studious, self-proclaimed good girl and could cleverly adjust herself to the changing situation.

Julianne wanted to be a doctor and never had the dream to become an actor. Although she never ever attended the theatre, she was an avid reader and this hobby of reading led her to participate in several plays in her school. Deeply impressed by her performances in the plays, her English teacher encouraged Julianne to pursue a theatrical career and she took the suggestion seriously. Her parents also supported her decision, but advised her to take training at the university to become properly equipped for the profession with a college degree.

Accordingly, she earned a Bachelor of Fine Arts (BFA) from Boston University in 1983 and moved to New York City soon thereafter.

In New York, she took the job of a waitress, registered her stage name with Actors’ Equity Association and began her career with off-Broadway and appeared in Caryl Churchill’s Serious Money at the New York Shakespeare Festival Public Theatre and also played the role of Ophelia in Hamlet, staged by the Guthrie Theatre. During that period she also began her career with a series of television roles and her first screen role came in 1984, in an episode of The Edge of Night, followed by As the World Turns, in which she played the dual roles of half-sisters, Frannie and Sabrina. Soon she made her cinematic debut as a mummy's victim in Tales from the Darkside: The Movie (1990), which was a low-budget horror-comedy, with little impact.

But her next film, the domestic thriller The Hand That Rocks the Cradle (1992), in which she played the role of the ill-fated friend of the main character, brought her to wider public attention. After that, she again played the supporting role of Madonna’s love rival in the erotic thriller Body of Evidence (1992), which was strongly lambasted by the critics, although they noted that Julianne performed commendably matched with her famous screen partners in the film.

However, in the same year, she was acclaimed for her performance as a gentle waitress in Benny & Joon (1993) and also appeared briefly as a doctor in one of the biggest hits of the year The Fugitive (1993), the crime-thriller starring Harrison Ford and directed by Andrew Davis. But her role of Marian Wyman in Robert Altman’s Short Cuts (1993) proved to be Moore's breakthrough role, as her performance was highly praised by the critics, along with Todd McCarthym, who also predicted that her monologue, delivered naked from the waist down, would be the most discussed scene of the film. As predicted, the film was awarded at the Venice Film Festival, Julianne received an individual nomination for Best Supporting Female at the Independent Spirit Awards and the most talked about monologue scene earned her a degree of notoriety.

Short Cuts was one of the three successive films that boosted Julianne’s reputation as an actor. It followed Vanya on 42nd Street (1994), directed by the famous French film director Louis Malle, in which her performance as Yelena was described as outstanding by the global magazine Time Out and she earned the Boston Society of Film Critic award for Best Actress. After that, she appeared for the first time in the leading female role in Todd Haynes’ low budget film Safe (1995), performing the role of Carol White, an affluent but unhappy housewife who develops multiple allergic reactions to her environment.

It was one of the most arresting and accomplished films of the 1990s, which perhaps for the first time established Julianne’s credentials as the finest actress of her generation and she earned an Independent Spirit Award nomination for Best Actress. However, Julianne had to lose a considerable amount of weight to match the role. But the process made her physically weak and ill and she vowed never to change her body for a film again.

After appearing in the comedy-drama Roommates (1995) and portraying the role of the pregnant girlfriend of Hugh Grant in the romantic comedy Nine Months (1995), Julianne also appeared in the commercially successful thriller Assassins (1995), along with Sylvester Stallone and Antonio Benderas. However, in the next year, she appeared only in the poorly reviewed Merchant Ivory period film Surviving Picasso (1996), in which she portrayed the artist Dora Marr, opposite Anthony Hopkins. But it became a key point in Moore's career, when she was cast by Steven Spielberg as Dr Sarah Harding in his The Lost World: Jurassic Park (1997), the sequel to his 1993 blockbuster Jurassic Park. Although it was a physically demanding role, Julianne enjoyed the job. The film finished as one of the ten highest-grossing films in history to that point and made Moore a sought-after actress in the film industry. During the production of The Myth of Fingerprints (1997), her second film released in that year, she met her second husband, director Burt Freundlich, whom she married later, on 23 August 2003.

Moore achieved more significant recognition in the late 1990s. Her decision to accept the proposal of Paul Thomas Anderson, a young and unknown director with only one feature credit to his name, proved to be a wise one. She was impressed with the exhilarating script and accepted to play the role of Amber Waves, a leading porn actress and mother-figure who longs to be reunited with her real son in Boogie Nights (1997), which centres on a group of individuals working in the 1970s pornography industry. For her wonderful performance in the film, Julianne earned her first Academy Award nomination for Best Supporting Actress, along with a nomination at the Golden Globe. She also played an erotic artist in Big Lebowski (1998), which subsequently became a cult film. In Gus Van Sant’s Psycho (1998), a remake of Alfred Hitchcock’s classic film of the same name, she played the role of Lila Crane, which received poor reviews and was criticised as one of her pointless outings.

The year 1999 started with a bang for Julianne Moore, as her portrayal of Mrs Laura Cheverly in An Ideal Husband (1999) earned her a Golden Globe nomination for Best Actress in a Musical or Comedy. In the same year, she appeared as an adulterous wife in 1940s Britain in The End of the Affair (1999) and received her second Academy Award nomination, her first nomination for Best Actress, as well as nominations at the Golden Globe, BAFTA and Screen Actors Guild (SAG) awards. She then enjoyed another collaboration with director Paul Thomas Anderson in Magnolia (1999), chronicling the lives of multiple characters over one day in Los Angeles and ended the year with another great performance as a grieving mother in A Map of the World (1999).

The year 2002 marked a high point in Moore's career, as she was nominated for two Academy Awards in the same year. Apart from a Best Actress nomination for her stunning performance in Far from Heaven (2002), in which she played a 1950s housewife whose world is shaken when her husband reveals he is gay, she also won the Best Actress award from 19 different organizations, including the coveted Venice Film Festival. Her second Oscar nomination in the same year came for The Hours (2002), in which she co-starred with Nicole Kidman and Meryl Streep and played a troubled 1950s housewife with a loving husband, whom she does not love, with a suggestion that she might have been happier living as a lesbian. Her other important films during the decade also include Laws of Attraction (2004), a courtroom based romantic comedy opposite Pierce Bronson, which was strongly panned by the critics; The Forgotten (2004), a psychological thriller, in which she played a mother who is told her dead son never existed; Children of Men (2006), a highly acclaimed dystopian drama; and Next (2007), a science fiction thriller, co-starring Nicolas Cage and Jessica Biel.

However, Julianne was fascinated with her leading role in Savage Grace (2007), portraying the true story of Barbara Daly Baekeland, a high society mother who was too much attached to her son, who grew into a narcissistic, hedonistic, inverted basket case and ultimately murdered the mother. She collaborated with Todd Haynes for the third time, when she appeared in his I’m Not There (2007), exploring the life of Bob Dylan. In the film, Julianne played the role of Alice Fabian, representing Joan Baez, who felt betrayed by the young talent for whom she had opened the doors. Shortly afterwards, she appeared in fashion designer Tom Ford’s directorial debut A Single Man (2009) as Charley, a woman in love with her gay best friend. While the film was selected as one of the top ten films of 2009 by the American Film Institute, Julianne received her fifth Golden Globe nomination for her performance in the film.

In her later films, Julianne appeared as a woman who cheats on her lesbian partner in The Kids Are All Right (2011), as an unhappy married woman in Crazy, Stupid, Love (2011), as the leading lady in The English Teacher (2013) and also in Non-Stop (2014), an action thriller set abroad an aeroplane. However, she won the Best Actress Award at the Cannes Film Festival, along with a Golden Globe nomination for her grand performance as Havana Segrand, an ageing actress receiving psychotherapy in David Cronenberg’s black comedy Maps to the Stars (2014). With her success at Cannes, Julianne Moore created history as the second actress after French actress Juliette Binoche to win Best Actress awards at the Big Three film festivals, namely Berlin, Cannes, and Venice.

Nevertheless, her performance as Alice Howland, the leading role of a linguistics professor diagnosed with early onset Alzheimer’s disease in Still Alice (2014), ranks among the most acclaimed of her career. For watching documentaries on the disease and interacting with patients at the Alzheimer’s Association, she toiled hard and spent four months training for the film and was awarded the Academy, Golden Globe, BAFTA and Screen Actors Guild Award for Best Actress. After a one-year absence from the screen, Moore portrayed a dual role of a wife and her twin sister in the dark comedy Suburbicon (2017), followed by Gloria Bell (2018), After the Wedding (2019) and The Glorias (2020), in which she performed as the feminist icon Gloria Steinem.

With more than a hundred acting credits under her belt and awards ranging from an Oscar to an Emmy to three Golden Globes, Julianne Moore is especially known for her meticulous portrayal of complex women and sympathetic portrayals of women at odds with their surroundings. Her long career has been nothing short of illustrious, but she always seems to make time for other things of importance in life like family, charity and writing children's books. In one of her books for the children, titled Freckleface Strawberry, she depicted her childhood experience of bullying for her red hair and freckles. Her other books for children included My Mom Is a Foreigner, but Not to Me (2013). She also penned several sequels, the first volume of which was adapted as a stage musical in 2010.

In her personal life, Julianne Moore met actor, producer and stage director John Gould Rubin in 1984 and married him two years later, on 3 May 1986. However, they were separated in 1993 and their divorce was finalised on 25 August 1995. Later, she began a relationship with Bart Freundlich, her director of The Myth of Fingerprints, in 1996. The couple have a son in December 1997 and a daughter in April 2002. Subsequently, they married on 23 August 2003 and are residing in Greenwich Village, New York City.