Starting as a finger-picking folkie and winding up as a jazz-savvy experimentalist, Joni Mitchell has brought a sharp eye, light touch and an agile trill of a voice to her songs, which have often dissected her romances and skewered myopic government. A wealth of musicians - from Tori Amos to Prince, from Joanna Newsom to Iron & Wine - have acknowledged her influence.

An only child, Roberta Anderson grew up in Saskatoon, Canada. At age nine she was stricken with polio. Defying doctors' predictions that she would never walk again, she recovered after spending nights in the children's ward singing at the top of her lungs. Throughout her childhood, she was involved in art and music, teaching herself to play guitar from a Pete Seeger instruction book. When she enrolled at the Alberta College of Art in Calgary, she took a ukulele with her and began playing folk music.

She soon moved to Toronto, where she began performing on the local folk scene and gave birth to a baby girl. At the time, the social stigma of being an unwed mother was so intense that Mitchell didn't even tell her parents about the baby. Without money, a job, or even a home, in 1965 she entered into what she later termed "a marriage of convenience" to folksinger Chuck Mitchell. They moved to Detroit, where Mitchell felt she had no option but to place her daughter, named Kelly Dale Anderson, up for adoption. She and Chuck Mitchell soon divorced.

Mitchell became a critical sensation on Detroit's folk scene, and her notices led to a series of successful engagements in New York. On the strength of her articulate songs and compelling perfor2 mance style, Reprise Records signed her. In late 1968 Judy Collins had a hit with Mitchell's "Both Sides Now." (In 1991 Carly Simon turned the song's lyrics into a children's book.) Collins' Wildflowers album also contained a cover of Mitchell's "Michael From Mountains"; the British folk-rock band Fairport Convention recorded Mitchell's "Eastern Rain"; and Tom Rush recorded "The Circle Game." Thanks to the buzz created by this ubiquity, Mitchell's debut, Song For a Seagull, coproduced by David Crosby, sold fairly well. It's more mature follow-up, Clouds (Number 31, 1969), sold even better.

Mitchell's style was emerging, and it was unique. Pensive and lilting, her songs offered a bit of philosophy, and were unafraid of positing points of personal romance. She had moved to Los Angeles, becoming a key component of the Laurel Canyon scene of singer-songwriters. Along with area residents as Crosby, Still & Nash, the Mamas & Papas, and Jackson Browne, she helped create the leafy sound of the early 1970s California. Ladies of the Canyon, a reflection of the lives around her (Number 27, 1970) went platinum, yielding a minor hit single: "Big Yellow Taxi" (Number 67, 1970) (which Janet Jackson sampled nearly 30 years later in her hit "Got 'Til It's Gone").

Mitchell's next platinum album was the critically acclaimed Blue (Number 15, 1971), which featured "Carey," "My Old Man," and "The Last Time I Saw Richard." That album included contributions from friends such as James Taylor (purportedly the subject of "Blue"). Mitchell had fallen in and out of love with Taylor and Graham Nash during these years; her personal life became fodder for her art, and the articulation with which she accounted for her heartbreak was deep. Blue is seen as the zenith of confessional songwriting, illustrating the joys and woes of romantic relationships. She played guitar and piano on most of the disc, but, uniquely, she also used a dulcimer on a few tracks. She'd learned how to play the easily portable instrument while living in Greece earlier in the year.

For the Roses (Number 11, 1972) went gold and contained another minor hit, the twangy "You Turn Me On (I'm a Radio)" (Number 25, 1972). The highest-charting album of Mitchell's long career remains 1974's Court and Spark (Number Two), which yielded the hit single "Help Me" (Number Seven, 1974). By this time, Mitchell's sound had grown from simple, unadorned acoustic guitar and voice into a sophisticated blend of jazz, folk and pop, replete with horns, keyboards, and complex backing vocal arrangements performed by Mitchell herself. Tom Scott and the L.A. Express, an agile electric jazz outfit, helped her flesh out a few of Court and Spark's rather elaborate arrangements.

The approach alluded to Mitchell's future direction with its overtly swinging version of Lambert, Hendricks & Ross' "Twisted," Mitchell's first recorded cover. The L.A. Express helped Mitchell deliver this new sound to her audience, captured on the live album Miles of Aisles (Number Two, 1974) and also participated in parts of The Hissing of Summer Lawns (Number Four, 1975). The singer's song structures were becoming more sophisticated and gorgeous. But her lyrics were a bit too ambitious for some critics, and Summer Lawns suffered some harsh reviews. Today the album is cited as influential by many artists, including Elvis Costello and Cassandra Wilson, particularly the tracks "Edith and the Kingpin" and "Shades of Scarlet Conquering". Mitchell wasn't shy about experimentation. "The Jungle Line" was probably the first pop record to use Burundi drums.

Though smoother and instrumentally spare, Hejira (Number 13, 1976) was another gorgeous disc that baffled some critics. It centered on travel and restlessness while tackling issues of commitment from a uniquely feminine perspective. Around Thanksgiving of that year Mitchell appeared at the Band's farewell concert in San Francisco, and was part of the filmed documentary, The Last Waltz.

In light of her previous two records, the double-disc Don Juan's Reckless Daughter (Number 25, 1977) was a logical if mysterious next step. Some critics felt that her lyrics had grown more convo3 luted and vague; indeed, Mitchell was using song structures far more ambitious and rich than the straight singer/songwriter confessional mode. Still, contrary to the then-prevailing view, Don Juan's Reckless Daughter was not all wild experimentation; in fact, half of its tracks (for example, "Talk to Me," "Off Night Backstreet," "Jericho") might have worked on any previous Mitchell album. But with jazz musicians Larry Carlton and Wayne Shorter working in cahoots with a group of Latin percussionists (including Airto), Mitchell was once again scouting new musical territory. "The Tenth World" and the side-long "Paprika Plains" were poetry soundscapes.

Perhaps indirectly, Don Juan led to Mitchell's most daring and most controversial project, her work with jazz bassist and composer Charles Mingus. Then dying of amyotrophic lateral sclerosis (Lou Gehrig's disease), Mingus invited Mitchell to collaborate with him. She set lyrics to some of the last melodies he wrote, composed the rest of the material herself, and released Mingus in 1979 not long after the bassist's death. It received mixed reviews but went to Number 17, an incredibly high chart position for a jazz album and a testament to Mitchell's fans' enduring interest in her work.

The live album Shadows and Light (Number 38, 1980), which featured a band comprise of Weather Report's Jaco Pastorius, jazz-rock guitarist Pat Metheny, and the a cappella group the Persuasions, also met mixed reviews.

Years later, Mitchell repeatedly and adamantly expressed no regrets about the rocky course she set. "I would do it all over again in a minute for the musical education," she told Rolling Stone. In 1982 Mitchell released her first album for Geffen, Wild Things Run Fast (Number 25, 1982), a more pop-oriented album that featured a cover of Elvis Presley's "(You're So Square) Baby I Don't Care" (Number 47, 1982). That year she married her bassist, Larry Klein. (They divorced in 1992.)

With Dog Eat Dog (Number 63, 1985), Mitchell's work showed a new emphasis on social commentary. Coproduced by Thomas Dolby, the album featured appearances by Michael McDonald ("Good Friends") and actor Rod Steiger (as a money-grubbing evangelist on "Tax Free"). Chalk Mark in a Rainstorm (Number 45, 1988) - with a guest roster that included Peter Gabriel ("My Secret Place"), Willie Nelson, Tom Petty, and Billy Idol ("Dancin' Clown") - was hailed by some critics as a return to form. Throughout the '80s Mitchell all but abandoned the concert stage. Her hastily arranged acoustic set at the 1986 Amnesty International benefit (she was a last-minute substitute for Pete Townshend) was cut short when the crowd, obviously unfamiliar with her work, booed her.

Mitchell experienced a resurgence of sorts with the 1990s, due to a confluence of events: a trio of albums generally considered among her best, her finding and reestablishing a relationship with the daughter she had given up for adoption, and a flurry of industry accolades and honors. Fans and critics swooned over Night Ride Home (Number 41, 1991), an album of readily accessible albeit sophisticated jazz-tinged pop. Three years later, Turbulent Indigo (Number 47, 1994) was released to glowing critical response and a Best Pop Album Grammy. While promoting that album, Mitchell disclosed that she was suffering from post-polio syndrome, a neurological condition related to her childhood bout with the disease that made it difficult for her to perform. Because her repertoire includes more than 50 different tunings, Mitchell was considering quitting the stage until she obtained a Roland VG-8 computerized guitar that eliminates the need for retuning.

In 1995 Mitchell became the fourth artist to receive Billboard's Century Award (previous recipients were George Harrison, Billy Joel, and Buddy Guy). It would seem that the award was made for Mitchell, since it recognizes artists who have not been accorded the acknowledgement they deserve. Two years later, Mitchell was reunited with her daughter, Kilauren Gibb, and a grandson. Though Mitchell had been quietly seeking her daughter and had written, however obliquely, of the matter in several songs (Blue's "Little Green" and Wild Things' "Chinese Café"), Kilauren began to suspect the connection when she received information about her biological parents that seemed to match 4 facts posted on a fan's Joni Mitchell Web page. Mitchell skipped her 1997 induction into the Rock and Roll Hall of Fame because she wanted to spend more time with her newly discovered family on her first Mother's Day.

Taming the Tiger (Number 75, 1998) was another critical triumph, followed in 2000 by a concept collection of standards concerning romance, Both Sides Now (Number 66, 2000). Using orchestral and big-band backing, Mitchell tackled such classics as "At Last," "Stormy Weather," "You're My Thrill," and "You've Changed," with two of her older songs, "Both Sides Now" and "A Case of You." Both Sides Now received the Best Traditional Pop Vocal Album Grammy.

In the late Nineites, Mitchell became a bit more visible, appearing on television and performing in concert. In 1998 she undertook a limited tour with Bob Dylan, and in 2000 she toured to promote Both Sides Now. That spring TNT presented "An All Star Tribute to Joni Mitchell," on which k.d. lang, Cassandra Wilson, Elton John, Richard Thompson, James Taylor, Wynonna, and others performed her music.

Mitchell has produced or co-produced each of her albums since her debut and has maintained control of her master recordings and her publishing from the beginning of her career. An accomplished painter and photographer, she created the art for each of her album covers, and her artwork has been exhibited throughout the world. Her first major career retrospective, Voices - The Work of Joni Mitchell, opened at the Mendel Art Gallery in Saskatoon in June 2000.

A lifetime of smoking put a deep mark on Mitchell's voice, but the husky tone it boasted during the recording of 2002's Travelogue, made with an orchestra and jazz associates Herbie Hancock, Wayne Shorter, and Brian Blade, was an apt fit for a glimpse back at a life's worth of work.

In 2007 Mitchell collaborated with the Alberta Ballet in Calgary, Canada on The Fiddle and the Drum. Also that year, Mitchell featured her anti-war in an installation called Flag Dance, which had an eight-week run at L.A.'s Lev Moross Gallery, and she released her first album of new material in seven years, Shine.

Two engaging studies of Mitchell's life and work also surfaced as the decade came to a close. Girls Like Us, by Sheila Weller, was an insightful overview of three pop women, Carole King, Carly Simon, and Mitchell. It arrived in the spring of 2008. The next year found Michelle Mercer's Will You Take Me As I Am in the racks; it's an investigation into the singer's Blue period.

Portions of this biography appeared in The Rolling Stone Encyclopedia of Rock & Roll (Simon & Schuster, 2001). Jim Macnie contributed to this article.