Single girls weren't supposed to have sex. It was a smart career move for Gurley Brown, who took over Cosmopolitan magazine after her book's success, which has flourished ever since.

And to mark the 50th anniversary of Sex and the Single Girl, it has been republished with a new introduction. For its time, the book was bold, in that it encouraged single women to celebrate their bachelor status.

The single girl was the new glamour girl, Helen affirmed. And she rebuffed the idea that 'nice' single women had no sex life.

"She has a better sex life than most of her married friends. Her choice of partners is endless and they seek her. They never come to her bed duty-bound."

Helen's ideal single woman is no sentimentalist. Have no truck with unemployed men. And, please, avoid any man with sex problems.

She describes herself as having been a plain, mousy girl from Little Rock, Arkansas who had to work hard to make herself into a metropolitan sophisticate.

She draws openly on her own experience and speaks of her many pre-marital affairs, all of which brought her lessons in self-awareness.

There is an element in Helen Gurley Brown of the American self-improvement manual. Discipline yourself and make yourself into something. The single girl can have sex and love and everything, but should work at it, too.

She should have her own apartment. She is open about having liaisons with married men.

"During your best years," she writes, "you don't need a husband . . . marriage is an insurance for the worst years of your life." Married men can really appreciate a girl, she says. But don't expect them to leave their wives. If they were going to do so, they'd have done it already.

Many wives are idle and self-absorbed and can't be bothered looking after their men folk, so why shouldn't single girls benefit? But do insist that your married lover brings you presents.

How dated is all this? Post-feminism, I think most women would be embarrassed to sound quite so materialistic and hard-edged. Yet the omissions are as interesting as the inclusions.

Helen encourages women to flirt adventurously and to be firm in turning down any of the aforementioned losers who start fooling around. But there is no reference to sexual harassment, or to rape, or male violence.

Helen takes it for granted that women have the emotional, and the sexual, power to call the shots: that a woman has every entitlement to pull a man if she wants him - but that she will be perfectly capable of putting him in his place if she doesn't want him.

Helen never sees women as victims. Paradoxically, it is only since the sexual revolution that she helped to launch that this emphasis on female victimhood has had such a focus.

Why, flirting itself is now regarded as sexual harassment on many a campus, and in many a forum of employment.