Arielle Green, a publicist in Manhattan, knows what most of her friends earn, whether it is $28,000 a year or $100,000. And she does not seem particularly shy about disclosing her income ($30,000 a year, plus overtime).

At 22, Ms Green, like her friends, is less afraid to flirt with what many over 35 consider the last taboo in American life: discussing salary openly with friends and colleagues.

"There's just more of a feeling of openness in discussing what you make," Ms. Green said. Her friends, she said, consider frank talk about income a valuable tool. It helps them strategise — when to push for a raise, when to start looking around. It even helps them figure out plans for a Friday night, whether the assembled cast is better suited to a brick-oven pizzeria or Buddakan.

Yes, elders find it strange. "My parents wouldn't have this conversation with friends," she said. For them, Ms. Green said, "it's very hush-hush. You don't talk about money, politics, or religion with friends. But in this generation, it's important."

For people old enough to remember phone booths, a blunt reference to salary in a social setting still represents the height of bad manners. But for many young professionals, the don't-ask-don't-tell etiquette of previous generations seems like a relic.

For them, salary information is now fair game, at least among friends. Many consider it crucial to prosper in an increasingly transient, winner-take-all workplace — regardless of the envy that full disclosure can raise. Besides, when the Internet already offers a cornucopia of personal information, it almost seems coy to keep personal income private.

As Ilana Arazie, 32, an online video producer for a media company in Manhattan, said: "If we can talk about how many orgasms we have with our mate, why can't we discuss how much we make?"

While salaries may be disclosed casually among friends, that doesn't mean most young professionals brag about their incomes at a cocktail party. There is still an etiquette to sharing the information — a proper way to divulge. For instance, most young people don't tell their cubicle mates, according to a 2007 study for Money magazine by the sociologist Jeanne Fleming and the writer Leonard Schwarz.

Still, young workers seem somewhat less likely to adhere to this convention than older ones. The study found that 90 percent of those over 35 who were surveyed agreed with the statement "you should never let your co-workers know how much you make," while 84 percent of subjects under 35 agreed.

But between friends almost anything is fair game. Beth Kobliner, the author of the best-selling "Get a Financial Life: Personal Finance in Your Twenties and Thirties," said she had noticed that many young people now "have no idea what their boomer parents earn, but know every intimate detail about their close friends' salaries, 401(k)s and debt loads."

She attributes the increase in openness in part to a shared sense of struggle by people in their 20s, who have come of age in a turbulent economic time, gyrating from the dot-com boom to the post-September 11 gloom, to the housing bubble to the credit crunch.

"There is a bunker mentality," Ms Kobliner said. "They've had it rough, jobs are precarious and debts are outrageous."

Bill Coleman, the chief compensation officer of Salary.com, which tracks income figures for numerous occupations by ZIP code, said that he had noticed more candor about income among those who live by social networking than among those who don't — what he calls the "MySpace/Facebook rift". And, he said, the new openness on salaries is reflective of a deeper acceptance of networking, offline as well as online.

"This is a generation that is much more attuned to teamwork, collaboration and sharing information," he said.

"Everything they do is a kind of group event. How do you know, when you get your first job offer, if $45,000 is a good offer, a bad offer or an OK offer? You go to your friends."

Several workers under 35 said that greater salary transparency among friends only makes sense in an age when there is so much information freely available online. Young professionals, in fact, have all sorts of ways to find out how much their friends make, even without asking. Associates at law firms anonymously report their own salaries to websites like www.greedyassociates.com. Every bonus season, Wall Street analysts send one another Excel spreadsheets, based on published reports and word-of-mouth, that detail which banks are paying what.

Related taboos already started to crumble over the last decade, as housing prices exploded, particularly in cities like New York and San Francisco, and people suddenly started to consider it innocent dinner-party banter to ask someone, to the dollar, what they paid for their two-bedroom condo.

Rebecca Geller, who works in media relations for green technology companies in San Francisco, recalled a recent brunch with two friends. One, a school administrator, was hoping to find a new job that paid at least $40,000 a year. He wanted to know if the other two people at the table — Ms Geller, 29, and a first-year lawyer — thought he was lowballing himself, asking, "Why, what do you guys make?" The truth hurt. The lawyer, a bit sheepishly, admitted that he made $130,000.

"There was definitely an awkward silence," Ms Geller said. Many professionals interviewed said that they believe salary talk is best confined to friends within the same tax bracket, to spare feelings. Others, however, insisted that a little generosity by the haves could help stave off jealousy by their have-not friends. Some young Wall Street professionals said that since everyone knows everyone else's bonus, it is common for friends with the biggest paydays to celebrate by picking up the cheque at a restaurant or nightclub.

Still, there are good reasons that generations of parents have instructed their children to keep quiet about money, social scientists say. In a meritocratic country, money has always been the great divider, the primary way Americans connote status. Thus it is impossible to engage in a conversation about income that is entirely innocent, said Herb Goldberg, a clinical psychologist in Los Angeles who has written about financial issues.

"When people talk about money," he said, most people traditionally have presumed that there is "a motive behind it, and the motive is what makes it seem impolite". People bombarded with unwelcome salary information, or pressed to disclose it, assume someone is raising the topic to subtly brag, or put someone else down, he said.

But social scientists say that some young people have generation-specific motives for broaching this touchy subject. Robert Frank, an economics professor at Cornell, said that an open flow of information is deemed crucial by young professionals who think of themselves as free agents, not company men.

"People move between jobs a lot more now than they used to," Dr. Frank said. This mobility alone increases the instances that salary might come up among friends. "If you change jobs, that's news," he said. "If you get a better salary, that's the explanation of the news: 'They're paying me 80 grand, the last place only paid me 65'."