Former Cosmo editor Helen Gurley Brown dies at 90

>>> long before "mad men" gave us peggy olson there was helen gurley brown a real life pioneer in the advertising world who took all that knowledge and put it to work in "cosmopolitan" magazine. in the early days feminists chafed at her unrelenting focus on catching, pleasing, and keeping a man but later came to embrace her embrace of sex for single girls, actually all girls of all ages. helen gurley brown died today at age 90. we get a look back tonight from nbc's kate snow .

>> reporter: before there was " sex in the city " there was " sex and the single girl ."

>> well, i didn't write the book to help us. i wrote it to help the unmarried women in this country.

>> reporter: natalie wood and tony curtis starred in the movie but it was inspired by helen gurley brown 's 1962 best seller, a frank and forward dating guide that encouraged women to enjoy being single. brown was as bold as her headlines and dating columns, the consummate new yorker in zebra print and big earrings.

>> i think that helen really helped create today's modern woman. i don't think that women would be in the careers that they have, that they would be ceos today if there hadn't been helen gurley brown . because helen said, you can do it.

>> reporter: she was at the helm of " cosmo " for more than three decades, took an ailing magazine with a small circulation, and transformed it into an international brand, the bible for single girls as its publisher boasted. she wasn't without critics. when a "new york times" writer suggested that " cosmo " was a woman's answer to "playboy" brown fired back saying the magazine was for young women who love men and children but don't want to be identified solely as wife, girlfriend, and mother.

>> she was a part of the women's liberation movement , of the 1960s , and that paved the way for real gains toward equality for all women.

>> reporter: in a 2003 appearance on the "today" show, she talked about growing old.

>> i think it is desperately old. 60s kind of you can be frisky and run around and who pays much attention anymore. used to be 40. now it's gone up to 60. but, 80, please. it's called give me a break.

>> at 80 she was still taking tango lessons. at 90 she was still overseeing 64 international editions of " cosmo ." life here will somehow not seem the same without her near daily arrival, a statement from hearst said. she'll be remembered a ceo said as the quintessential cosmo girl . kate snow , nbc news, new york.