Cosmopolitan magazine holds a spot as one of the most successful women's magazines of all time. In the late 1990s it boasted a circulation of 2.4 million readers in the United States, and an impressive 29 editions in other languages. Its distinctive, come-hither covers seem designed more to catch a man's eye than any potential female newsstand browser, and inside its pages features give women very specific advice on how to lure—and keep—a man. Yet the Cosmopolitan ideology—revolutionary in the 1960s, fitting in perfectly with the liberated-women zeitgeist of the 1970s, and setting the big-haired tone of the 1980s—was the creation of one very female mind: Helen Gurley Brown. The author of the bestselling Sex and the Single Girl (1962), as Cosmopolitan editor, Brown deployed her array of self-improvement strategies into a monthly format that made her name synonymous with the magazine and enshrined Cosmo, as it...