What do Sting, Bill Gates and Warren Buffett have in common? All three have huge fortunes, and none of them is giving it to their kids.

Sting just revealed that most of his $300 million won’t end up with his six adult children. “I certainly don’t want to leave them trust funds that are albatrosses round their necks,” the musician told the Daily Mail in June. “They have to work. All my kids know that and they rarely ask me for anything, which I really respect and appreciate.”

Philip Seymour Hoffman, who died of a heroin overdose in February, left specific directives in his will, which was made public last month: His son should be raised in a large American city and “be exposed to the culture, arts and architecture” that such a setting offers. The will was created before the birth of his two younger children, but the actor deliberately didn’t give his $35 million to his children because he didn’t want them to be ” ‘trust-fund’ kids.” (They’ll be fine; his entire estate went to their mother, his longtime girlfriend.)

The rap on trustafarians – all those spoiled rich kids with more money than sense – is that they won’t make smart choices or live healthy, productive lives if they have unfettered access to a large inheritance. Celebrity chef Nigella Lawson has stated she has no intention of leaving a substantial inheritance: “I am determined that my children should have no financial security. It ruins people not having to earn money.”

Wealthy families have always struggled with this issue. But the same drama is now playing out on a smaller scale for millions of baby boomers, who are poised to give away $30 trillion over the next 30 years – the largest transfer of wealth in U.S. history, according to consulting firm Accenture. What used to be a private family matter has become a public discussion about wealth, privilege and personal responsibility. Who gets the big money? Should it be the heirs? Or are they better off without it?

Bill and Melinda Gates are giving a reported $10 million for each of their three children: pocket change compared with their $76 billion worth. Buffett’s three kids each have a $2 billion foundation funded by Dear Old Dad. The rest of his money? Going to charity, just like Gates and several other billionaires who have pledged their vast fortunes to improving the world.

As Buffett famously put it, the perfect amount to leave children is “enough money so that they would feel they could do anything, but not so much that they could do nothing.”

‘We probably struggled over this more than any other issue,” says a self-made multimillionaire in Washington. The businessman and his wife, worth hundreds of millions, grew up modestly in middle-class families and wanted to create a financial plan that would take care of their children – but not spoil them – if the couple died suddenly.

“We were horrified by what might happen if they had control of a large amount of money at a young age,” he says. “The more we stared at that, the more we became uncomfortable.”

Inspired by Buffett’s example, they created trusts for each of their now college-age children. Each kid has $2.5 million controlled by trustees, who can release money only for education, health care, a home purchase or a business start-up. Any unspent money in the trust will continue to be invested and grow.

Those restrictions remain in place until each child reaches age 40; after that, the money is all theirs to do as they please. In their 20s and 30s, the funds are there to get them launched; by 40, their parents assume they will be mature enough to use the money wisely or save it as a safety net.

The rest of the multimillion-dollar family fortune is going to a foundation, which will eventually be administered by the children, and can be used only for philanthropy. The kids are aware of the trusts and the planning that went into them.

“They really are thrilled with it,” their father says. “They want to be their own persons.” A huge inheritance, he believes, can be a lifelong trap for children of rich parents. “I didn’t want them to look in the mirror and say, ‘Who am I?’ ”

Jamie Johnson has spent his entire life around the very, very rich. In 2000, when he turned 21, the Johnson & Johnson heir inherited a huge amount of money – reported estimates put the figure at $600 million – from a family trust. Each of his five siblings received a similar amount, with no restrictions on its use. His 2003 documentary “Born Rich” was a study of his family’s money and other super-rich friends.

“When vastly wealthy people say, ‘I’m not leaving my kids any money,’ it’s typically not true,” Johnson said. Even when children don’t have immediate access to cash, they get the best schooling, housing, contacts and opportunities. “All of these are things that only rich families can do. These are all different ways of transferring wealth and influence,” he said.

Whether having so much money is good or bad for trust-fund babies depends on how the family has prepared the kids, on their personalities and on how well they handle the pressures of great wealth and the fear of disinheritance. For every party girl like Paris Hilton, there’s an Ivanka Trump, who got a business degree from Wharton and has parlayed her family’s money and famous name into a thriving career. Johnson used his inheritance to launch a filmmaking career and to live, all things considered, a relatively normal life in New York. “In my case, it turned out to be a great benefit,” he said.

Occasionally, wealthy parents put strict conditions on behavior and threaten to cut off their kids. Tori Spelling reportedly inherited just $800,000 of her late father’s estimated $600 million fortune; money tensions have been an ongoing issue between her and her mother, who controls the estate. In an interview with The New York Times this year, Candy Spelling explained that her daughter “would close a store and drop $50,000 to $60,000. I never did anything like that. She just went crazy.”

Most parents want to protect their children from the dark excesses of money – drugs, lawsuits, hangers-on, crippling self-doubt – and preserve the family fortune for future generations. That usually doesn’t work out: The first generation makes the money, the second spends the majority of it, the third drains the rest. Hence the old adage: “Shirtsleeves to shirtsleeves in three generations.”

Take, for example, the Vanderbilts. When he died in 1925, Reginald Vanderbilt had blown through more than $7 million (about $94 million in today’s dollars) of the railroad and shipping fortune that his grandfather had amassed. But there was still a $5 million trust for his two young daughters. One of the girls was Gloria Vanderbilt, who went on to earn her own $200 million fortune in design and decorating.

Gloria has told her son, Anderson Cooper, that he won’t get a penny from her. “My mom’s made clear to me that there’s no trust fund,” he told Howard Stern this spring. And Cooper’s fine with that: Unearned money, he said, is a curse. “Who’s inherited a lot of money that has gone on to do things in their own life?” asked the CNN star, who earns $11 million a year. “From the time I was growing up, if I felt that there was some pot of gold waiting for me, I don’t know that I would have been so motivated.”

So, what’s a loving parent to do?

Traditionally, the wealthy gave all their money to their children and grandchildren, then hoped for the best. Baby boomers, says Accenture managing director Bob Gach, are living longer and struggling to balance their own retirement needs and charitable interests with their children’s welfare.

“It’s this interesting confluence of demographics, longevity and accumulation of assets,” Gach said. He’s done well in his career and plans to leave some of his wealth to his 20-year-old son, some to his alma mater and some to his favorite causes. “I want my son to have the benefit of that, but I don’t feel I have to leave him every penny,” Gach said.

Accenture released an influential 2012 report looking at the estimated $12 trillion that boomers are currently inheriting from their parents and the estimated $30 trillion they will leave to their heirs and other institutions. These, of course, are the lucky ones – unscathed by the recession, still gainfully employed or retired with substantial savings.

Boomers are different from previous generations: more likely to give away money while they’re still alive, more concerned about their adult children finding and keeping jobs. Excess assets typically go into tax-protected trusts, which can be liberal or restrictive.

“Some people say, ‘I worked really hard for this money, and I don’t want my son to use it to live on a Caribbean island – I want this trust to be a safety net,’ ” said Nancy Fax, an estate and trusts expert in Bethesda, Maryland. “And some people say, ‘I don’t want to control from the grave.’ But there are really good reasons to leave a legacy in a thoughtful way – ways that promote productivity and healthy lifestyles.”

Many trusts are structured to distribute inheritances at predetermined ages. A common practice is to give a third at 25, a third at 30 and the balance at 35. Some inheritances are set up as “incentive trusts,” with provisions that require the heir to graduate from college, marry or hold a job for a specific amount of years before any money will be released.

Fax isn’t a fan of either: The future is hard to predict, and incentive trusts are full of loopholes. “It’s controlling and very, very difficult to define,” she said.

Another wrinkle: A lot of people don’t like to talk about money because they don’t want the kids to know how much they’re actually worth or what they might inherit. Although adult children in the United States have no legal rights to their parents’ money, it’s rare for heirs to get cut off with nothing. But that doesn’t mean they get everything.

Fax has a client who “loves his children very much, and he is actively looking for ways to leave his money to charity,” she said. The self-made entrepreneur has given his children a great education, monetary gifts and part of his business. “He feels blessed and he feels his children have been blessed. And he believes the excess should go to good works,” Fax said.

Kind of like Bill Gates. The world’s richest man won’t disclose the exact amount each of his three kids will inherit, but he told the Daily Mail in 2011 that it will be “a minuscule portion of my wealth.” They’ll get an “unbelievable” education and health care and the reported $10 million, which still puts them firmly in the One Percent – but not even close to their self-made father’s billions.

For that, they’ll have to found their own global empire, he said: “In terms of their income, they will have to pick a job they like and go to work.”