High-end consumption may revert to being a millionaire's club.

With consumers determined to save and their view of the American Dream in flux, growth in the luxury sector will increasingly stem from households with liquid assets of at least $10 million in the U.S. and $3 million in other countries, marketing experts said.

"The luxury business is the toughest I've seen it in 20 years," said Greg Furman, chairman and founder of The Luxury Marketing Council, whose 675 member companies include Baccarat, Baume et Mercier, Bergdorf Goodman, Blue Star Jets, Cartier, Montblanc, Movado, and Neiman Marcus.

Even many of the nation's rich are pruning spending on prestige goods. A new snapshot of 16,000 affluent Americans, who are among the wealthiest 10 percent with average assets of $3.1 million, shows about half will slash their budgets this year, repeating a pattern from 2008. This group also has average annual income of $315,000, according to "Luxury in a Recession," the study by marketing agencies Young & Rubicam and the Tom Julian Group, which was conducted nationwide in the third and fourth quarters of 2008.

"Luxury is evolving into exclusivity of experience; it is not only a product, it is a lifestyle," said Claudia D'Arpizio, a Bain & Co. partner in Milan. That's one reason top names like Giorgio Armani, Versace, Salvatore Ferragamo, and Bulgari have been developing luxury hotels and restaurants, added D'Arpizio, the lead author of Bain's "Luxury Goods: Worldwide Marketing Study 2008."

At the same time, the ranks of customers for accessible and aspirational luxury goods and services are thinning fast.

The picture isn't expected to brighten until there is a sharp upturn in home values, which lost $3.3 trillion in the U.S. last year, about half the value since peaking at $6.1 trillion in 2006, according to Zillow.com, a real estate marketplace.

Bain & Co. last month lowered its outlook for global luxury consumption, forecasting a fall-off this year that could go as deep as 15 percent compared with 2008.

"What happened in the fourth quarter—70 percent off isn't even enough anymore—is a lesson," said Pamela Danziger, president of Unity Marketing. Prestige brands, she added, "will have to go back to targeting rich people and give up the people [who were] trading up."

In this environment, Americans whose annual household incomes of $100,000 to $250,000 make them comfortable, but not rich, "will probably adjust their spending to the point where" less pricey, upscale brands "will benefit," Danziger said, citing J. Crew, Coach, DKNY, and Furla.

As a result, premium goods and services from jewels to designer apparel to luxury hotels to private jets are becoming the province of a more rarified group of consumers.

When John Gerzema, a trend forecaster and chief marketing officer at Young & Rubicam, met up with his former investment banker friends in February, he learned they were giving up their New York Yankees seats, selling their wine collections and taking their kids out of private schools. They were also drinking beer.

"We usually would have been drinking first-growth Bordeaux," Gerzema recalled. "This time, I was drinking Belvedere and grapefruit juice, and had the most upscale drink."