It was a blisteringly hot afternoon in September. A friend in her 30s had hauled herself out of bed after suffering from a painful inner-ear problem to go to her husband’s annual office barbecue.

This takes place at his chief executive’s stunning house on the beach in the Hamptons, America’s summer playground for the wealthy on Long Island. Ostensibly, it’s a happy occasion ? in as much as investment bankers ever experience happiness at corporate occasions. There are children running around, barefoot in the sunshine, and there is plenty of beer, wine and excellent food. It is usually an event that even the employees’ wives enjoy ? and, let’s face it, that can’t be said for many office parties.

Suddenly, the husband turned to his wife and said: “Can you take off your sunglasses?”

She was surprised. She had dressed in an enormous straw hat to fend off the sun, a pretty but simple sun-dress, flip-flops and enormous glasses to hide behind since she wasn’t feeling well.

“You look like Joan Collins,” said the husband.

There was a pause. “I’m blonde,” the wife replied, whispering furiously back. “How could I possibly look like Joan Collins?”

“You look unfriendly,” said the husband.

The wife took off her glasses, realising as she did so that she had broken one of the most important rules regulating the game of “corporate wife”. When it is your husband’s event, you don’t leave the house without first checking what he wants you to wear ? something best done days in advance in case you don’t possess a pair of cargo pants, or a Ralph Lauren polo shirt or your black-tie dress is too glitzy or too revealing and you are in danger of looking too attention-grabbing.

The list of rules goes on and you have to learn them if your husband is to get where he needs to get to, allowing you to get where you need to get to.

Thus the male author of a recent controversial piece in Forbes magazine who stated that careerist men don’t want to marry careerist women was, in one sense, right.

I have got to know my way round corporate New York a little in the past few years and what I have noticed is that very successful men here ? entrepreneurs, the chief executives of banks, private equity houses, hedge funds, real estate companies and so forth ? have one thing in common when it comes to their spouses: they choose very smart (American word for clever) wives. (Important note: depending on the age of the man, the women I refer to may not necessarily be their first or even second wife).

The women’s common denominator is this: they long ago ceased to be interested in furthering their own careers because, they figured, what would be the point of struggling, feeling tired and looking haggard for a few extra dollars when, if you snag the right guy, you can get a private jet and five houses with staff? Not to mention designer clothes, jewels, personal decorators, islands in the Caribbean, unlimited cash for “maintenance” or even “improvement” of the figure and face as well as a fun-filled diary, full of engagements with interesting, powerful people.

So who are they, these women, the New York corporate wives who know how to play the game? Well, perhaps the best way to look at them is from the vantage point of the men who select them.

I do not use the word “select” loosely.

There is a legend here about a well-known chief executive in the financial services industry, who, having tired of his first wife of 20 years, and then tired of the pretty but uninspiring models he subsequently amused himself with, sent out a list of requirements for a second spouse to his friends because he did not have time to search for the candidate himself. He was too busy flying round the world and making billions each year.

I have not seen the list but I know, generally, what he wanted.

He wanted someone who was smart enough to read him, in the same way every top-level executive needs a personal assistant smart enough to know, instinctively, when to speak, when to stay away and when to put a call through.

He needed this person to run his life seamlessly so that his time would never be wasted with menial tasks such as looking at an electricity bill, packing a suitcase or instructing the staff.

He needed someone glossy enough to reflect his glory and power but clever enough to know to not outshine him. In other words, she needed to know when to chatter away charmingly and when to shut up. She needed to be glamorous but not high-maintenance. Emotional neediness is a big no-no.

She needed, though he didn’t quite think of it like this, to make up for his defects because he had been so focused on making money that reading people socially was not one of his natural skills. She needed to know which designers, artists, decorators, authors and media people were “in”. She had to facilitate dinner parties at his various homes for such people so that he would be au courant, not to mention part of modern culture.

She must be the kind of woman who would never embarrass him by somehow denigrating him either in conversation or by dressing or behaving wrongly. She must share his interests, taking up golf if necessary (remember how Jack Welch’s second wife, Jane, became a scratch-golfer?) and chess or even cycling. (When Michael Eisner ran Disney, he used to host an annual cycling trip that guests had to train for frantically beforehand.) She must care about his children and a bit about hers if she has them ? but only to a point ? and certainly not more than him and the running of his houses and staff.

She needs, above all, to understand The Deal.

The Deal is that her life is about one thing only: him.

She must be there at the end of the day, looking good, drink in hand, ready to pleasure him with witty conversation or in other ways.

If not, she will be sacked. And since she will not have entered this relationship without having signed a pre-nuptial agreement, she knows exactly how she will be sacked and what assets she will be left with.

So then, who are they, these miracle-workers who pull off all of the above?

Well, as we know, they’re not Ellen Barkin, Claudia Cohen or Patricia Duff, all of whom tried out marriage with Revlon chief Ronald Perelman and were fired. Note, all of them made a crucial mistake: they worked for themselves as well as for him. Barkin acted, Cohen wrote and Duff was involved in politics.

Not Nicole Kidman. Far too A-type for Tom Cruise. Anyone notice the disparity between the amount of post-Tom Cruise movies generated by Kidman and Katie Holmes? The former won an Oscar while the latter produced a small, dark-haired baby called Suri.

And we can wonder too about journalist Suzy Wetlaufer, wife of Jack Welch. The former GE chief was quoted on Fox News saying that should he succeed in his bid to take over the Boston Globe newspaper, he would certainly not be appointing her as editor. “She needs to look after me,” he said.

Now to the success stories. Two who spring to mind are in their 30s. They genuinely enjoy tending to their husbands. Both are effortlessly stylish and beautiful. Both are listeners rather than talkers at business dinners, yet clearly they are up to speed with current affairs and their husband’s respective businesses. Both adore their husbands, whom they talk up at all appropriate moments but in a natural, non-unctuous way. Their husbands are two of the luckiest men in the world and they are sensible enough to know it.

Another example is younger than her husband by a decade or so. She is in her 50s and had a very successful career before meeting him and, thus, has no need to prove anything to anyone ? which again makes her an easy dinner companion and an asset to him. She is efficient and efficiency is what he likes. She is always “up”, never stressed and her husband has told me with some pride that he loves to hear her post-mortems of dinners because she is “so clever and a very good judge of character”. If she doesn’t like someone, or finds them a self-important bore, he will not invest with them, no matter how prominent the person. An important lesson there.

A fourth example is a sadder case. She is in her 40s and once had a glittering career but bravely, if stupidly, told people she was bent on marrying money. She fulfilled this ambition by marrying a much older man. “We go home to relax and she has to go home to work,” is how one of my friends has described the relationship.

Now one often sees her out at dinner parties on her own, pretending to look happy but failing. Her career disappeared with the marriage because it was, so her husband once informed me, inconvenient.

Naturally, people idly and meanly speculate when the marriage will end and how much of the pre-nup she will get. The rule of thumb in the billionaire set is that you only get what they term “meaningful” money if the union exceeds 10 years and produces children. If you do neither of the above, then you might get $5m and a small apartment. This is deemed consolation money and you will need it, since Manhattan for single women over 40 can be a brutal place.

Successful men here see females as expendable commodities. Some never bother to marry at all. Their number includes Teddy Forstmann, the corporate buyout specialist, Larry Gagosian, arguably the world’s most successful art dealer, and Jeffrey Epstein, the financier currently facing allegations of soliciting a prostitute in Palm Beach.

If all this sounds sad and cynical, well, welcome to the Big Apple. Personally I find nothing so ridiculous as the spectacle of middle-aged, single “tycoons” escorting models 30 years or more their junior to dinner. Yet I see it with alarming regularity. Still, just when one is on the point of despair about the bleakness of the whole scenario, you see something like I saw this summer. I was in a taxi going up Park Avenue when I spotted a very famous financial services titan, now in his 60s, who was crossing the street with his wife, also middle-aged and a formidable careerist in her own right. They were talking as if there wasn’t enough time in the world to say everything they wanted to each other. When they had finished crossing, they turned to walk down the pavement. He gently put his arm around her and she returned the favour. They looked at each other and giggled like teenagers.

I don’t want to name them because it was such an intimate moment. Suffice to say, it was a sight I shall never forget.

Vicky Ward is a contributing editor at Vanity Fair