The product of a strict convent education, Bujold dropped out to pursue an acting career. She studied her craft at the Quebec Conservatory of Drama before joining the Le Rideau Vert repertory company where she made her stage debut in "The Barber of Seville" and went on to star as "St. Joan".
Bujold made her screen debut in the small film "The Adolescents" (1964) before heading across the ocean to France. Director Alain Resnais saw her play Puck in a French production of "A Midsummer Night's Dream" and signed her to co-star opposite Yves Montand in "La Guerre est finie" (1965). Bujold made two more films in France, playing Alan Bates' love interest, an asylum inmate, in the cult hit "King of Hearts" (1966), and appearing in Louis Malle's "The Thief of Paris" (1967). For the latter, she was proclaimed the French film industry's "Discovery of the Year", winning the Prix Suzanne Bianchetti. She also caught the eye of US producers. Bujold played "St. Joan" in a 1967 NBC "Hallmark Hall of Fame" rendition of the Shaw play, and returned to Canada to star in "Isabel" (1967), the first of five films for then-husband Paul Almond. Bujold earned a Best Actress Oscar nomination for her work as Anne Boleyn in "Anne of a Thousand Days". Hollywood soon beckoned, but while she had worked with Resnais and Malle in France, in Hollywood she was cast as the young widow Charlton Heston wishes to make a married lady again in the blockbuster "Earthquake" (1974). In 1978, she was a doctor who discovers patients are being murdered for their body parts in "Coma".
By the early 80s, some of the prestige of her career had faded. Bujold fared well opposite Clint Eastwood in the thriller "Tightrope" (1984). She went on to become a member of Alan Rudolph's informal stock company, giving suitably cryptic performances opposite Keith Carradine in "Choose Me" (1984), "Trouble in Mind" (1985) and "The Moderns" (1988). Bujold was also memorable as Claire, the hard-living actress, opposite dueling twins (Jeremy Irons) in David Cronenberg's "Dead Ringers" (1988). But by 1992, she again had weak material, playing a married woman who catches the affections of Corey Haim in "Oh What a Night".
Bujold has starred in a few American TV-movies, including "Mistress of Paradise" (ABC, 1981) and "Red Earth, White Earth" (CBS, 1989). Bujold has occasionally performed classic roles on TV: "Antigone" (PBS, 1972) and Cleopatra in a "Hallmark Hall of Fame" rendition of Shaw's "Caesar and Cleopatra" (NBC, 1976).
From 1967 to 1973, Bujold was married to Canadian film director Paul Almond, who directed her in five films. Their son Matthew Almond is an actor and filmmaker.