Helen Gurley Brown at a book signing, 1963

Author and magazine editor Helen Gurley Brown was born in Green Forest, Arkansas on 18 February 1922 to Ira and Cleo (Sisco) Gurley, both schoolteachers. Though the family was poor, Cleo quit teaching to rear her two daughters. In Helen's early childhood, the Gurleys moved to Little Rock when Ira was elected to the state legislature. He was killed in an elevator accident when Helen was ten. Cleo struggled to support her children in depression-era Arkansas, first moving back with family in the Ozark region, and then taking Helen and her older sister Mary to Los Angeles in the late 1930s. In Los Angeles, Mary contracted polio, which strained the Gurley's already grim financial condition. Despite hardship, Helen excelled socially and academically. She was active in leadership positions in several high school clubs and graduated class valedictorian.

Helen Gurley spent a year at the Texas State College for Women and then returned to Los Angeles to put herself through Woodbury Business College. Cleo and Mary moved back to Arkansas but remained dependent on Helen's financial support, a situation which continued for the remainder of their lives. Helen graduated from Woodbury with a business degree in 1941 and took on a succession of secretarial jobs. The seventeenth job, at the advertising agency Foote, Cone, and Belding, was pivotal to Helen's future success.

Helen Gurley worked as executive secretary to Don Belding. During this time, she won a Glamour magazine contest for "Girls of Taste" that awarded her a vacation and a wardrobe. She had an active dating life, including a romance with prizefighter Jack Dempsey. Gurley's hard work captured the attention of her boss, and at the suggestion of his wife, Don Belding experimented, allowing Helen to write advertising copy. She succeeded at the task, and moved from secretarial work to copywriting. She wrote ads for several accounts, won prizes for her copy, and by the late 1950s had become the best-paid female copywriter on the West Coast.

In 1959, at the age of 37, Helen found a marriage partner in David Brown, a magazine and book editor who would become a film executive at the Twentieth Century Fox Studios, and later an independent producer. He was also an uncredited partner behind many of Helen's projects. After she found her advertising career stagnating at Foote, Cone, and Belding and then the Kenyon and Eckhardt Agency, it was David who encouraged her to write a book about her life as a single woman. The result, Sex and the Single Girl (1962), captured a zeitgeist of the early 1960s.

Bernard Geis Associates, a maverick publishing house, found great success with Brown's book, a guide to living single "in superlative style." It later published the wildly successful potboilers of Jacqueline Susann. Sex and the Single Girl, an advice manual that exhorted women to remain single and find fulfillment in an occupation and non-marital relationships with men, sparked national controversy and remained on the best-seller lists for months. Helen Gurley Brown made frequent personal, television, and radio appearances to promote the book. Rights to the title were sold to Warner Brothers at the highest price then ever paid for a non-fiction title. The film, Sex and the Single Girl (1964), starred Natalie Wood (as Helen Gurley Brown) and Tony Curtis.

Following the success of Sex and the Single Girl, David Brown and Bernard Geis Associates marketed Helen in a variety of enterprises. She wrote a syndicated newspaper advice column, recorded phonograph albums and radio spots, and wrote prodigiously. Her next book, Sex and the Office (1964), a racier advice manual and expose of a sex-filled world of secretaries, sold disappointingly in comparison to Sex and the Single Girl.

The Browns submitted proposals for a variety of works to keep up the momentum of Helen's popularity following Sex and the Single Girl: plays, television shows, other books, and magazines. Their proposal for a magazine for single women ("Femme") drew the interest of the Hearst magazine corporation. Though they did not want to start a new magazine for Brown, they made a trial agreement for her to try her format at their failing general interest magazine, Cosmopolitan. Brown officially became editor of Cosmopolitan in July 1965, and she brought dramatic changes to the first issue.

Brown converted the conservative Cosmopolitan to a female counterpart of Hugh Hefner's iconic Playboy magazine. She featured sexy cover models, controversial subject matter, and a hip sensibility that garnered a large audience quickly. While editing Cosmopolitan, Helen Gurley Brown authored The Single Girl's Cookbook (1969) and Sex and the New Single Girl (1971), continued to be a guest on many TV shows, and became one of Hearst's biggest success stories. Meanwhile, David Brown, along with partner Richard Zanuck, produced many successful films, including The Sting, Jaws, Cocoon, Deep Impact, and Chocolat.

In 1983 Helen wrote the best-seller Having it All, an advice manual and memoir in the style of Sex and the Single Girl. In the 1980s, she also had television stints as a regular on Good Morning America, a short-lived syndicated show A View from Cosmo, and was a guest on talk shows. She continued to edit the highly successful Cosmopolitan, which had by the 1980s grown to 300 pages, of which a hundred were highly lucrative advertisements. She oversaw expansion of the Cosmopolitan franchise into numerous international editions. In 1993 she wrote The Late Show, an advice manual and memoir about growing older. She published a writing guide, The Writer's Rules, in 1999, and in 2000 wrote her definitive memoir, I'm Wild Again.

Brown's career was often marked by controversy. Sex and the Single Girl, a celebration of independent womanhood published a year before Betty Friedan's The Feminine Mystique, sparked much dispute about women's place in pre-women's movement popular culture. In a literary world that had only recently seen the lessening of stringent restrictions on the portrayal of sex, Brown's emphasis on sex drew much opposition from conservative critics. However, by the late 1960s, she and her vision of adamantly man-crazy womanhood drew opposition from non-conservatives as well. The incipient women's movement targeted Brown's limited vision of liberation. Feminists criticized the sex-object "Cosmo Girl" and envisioned a mass media that reflected a greater range of possibilities for women than the pink collar, man-obsessed vision of Cosmopolitan. Brown's idiosyncratic notions of liberation and sexual freedom raised controversy in later years as well. In the 1990s, her dismissal of sexual harassment as a significant workplace problem and her indifference to the risk of AIDS for heterosexual women drew great wrath again from feminists. Brown nonetheless identified herself and her magazine as unfailingly feminist. She worked on behalf of the National Abortion Rights Action League in support of abortion rights and supported other feminist organizations and causes.

While Brown was frequently the target of criticism, in the last years of her life she also accumulated accolades. Her work at Cosmopolitan was recognized through her election to the Publishing Hall of Fame and a Henry Johnson Fisher Award. She was declared a New York City landmark, being a familiar presence on New York City busses heading from her Central Park West apartment to the Cosmopolitan office. Her admirers and friends included gossip columnist Liz Smith, television journalist Barbara Walters, mogul Malcolm Forbes, and New York Mayor Ed Koch.

In 1997 Brown gave up her editorship of Cosmopolitan to become editor-in-chief of international editions of the magazine. Far from a retiree, she remained a workaholic in her new job, enjoyed travel with David, who continued to produce hit films until his death in 2010, and still voiced "outrageous" opinions that made her a frequent presence in newspapers and magazines. In early 2012 she established the David and Helen Gurley Brown Institute for Media Innovation, donating $30 million dollars to collaborating institutions, Columbia University Graduate School of Journalism and Stanford School of Engineering. Helen Gurley Brown died in a Manhattan hospital on 13 August 2012.