Forget a sit-down dinner in a private restaurant room. Unfazed by the credit crunch and economic turndown, today’s wealthy elite are renting entire hotels, taking over resorts and booking every room on a cruise ship to guarantee that ultimate luxury: complete privacy for themselves and their guests. The entire party often travels by private jet or yacht, and the only thing expected of them is that they have a good time at the host’s expense. “If you can afford it, you want to be in an environment where there are no strangers,” says Fred Varnier, general manager of the Amanpuri Phuket resort, which occasionally rents out all 30 pavilions and 40 private villas for $100,000 a day to certain discreet parties. “They don’t want to let their hair down around people they don’t know.”

In the past, such all-expenses-paid extravaganzas typically took place only for weddings or extended family reunions. But now the growing ranks of the young and wealthy, as well as rich retirees who realize they can’t take their fortunes with them, are booking entire venues for less momentous occasions. At Rome’s Cavalieri Hotel, an American couple recently booked 48 of the 370 rooms for a toga party. For $140,000, the Ritz-Carlton New York can arrange a one-night “Friends With Money” package, which includes 15 executive suites with views of the city skyline or the Statue of Liberty and fireworks for 32 guests. A Russian oil tycoon blocked all 25 rooms onboard a Bora Bora cruise in March, inviting friends who had never been to Tahiti.

Sometimes people rent an entire hotel and leave most of it empty; a retired investment banker reserved the Hotel Rosa Alpina, a 50-room mountain retreat in the Dolomites, for 18 friends to celebrate his wife’s 50th birthday, with helicopter rides to Venice, massages in heated tents and a two-star Michelin chef on call for picnic lunches. One of the first bookings for The Regent Bordeaux, scheduled to open in June, was from a Middle Eastern family planning a sightseeing trip who rented the entire top floor so the children and nanny could spread out. “There are a lot of people telling themselves, ‘I have more money than I am going to spend in this lifetime; why not enjoy and share with people close to me?’ " says Kenan Simmons, a vice president at the Leading Hotels of the World. “The older generations were a little more conservative and wanted to keep it in the bank. A lot has to do with the generation.”

Often they are drawn by a hotel’s particular perks. Tucked inside the Mayfair is the largest private theater in London, with seats for 201. “We have family reunions where you can screen old films and photographs,” says Christine Howarth, the head of guest relations. Badrutt’s Palace Hotel in St-Moritz, Switzerland, once closed off the entrance for a group that hired circus acrobats and a live human cannonball to perform in the lobby. Amanpuri, which owns 30 yachts for its guests’ exclusive use, has launched flotillas for private parties to island-hop. And guests at Madeira’s Choupana Hills Resort and Spa in Portugal, which hosts an annual jazz festival in September, can book the local concert hall for a night of improv any time of year.

Even hoteliers have been surprised by the growing interest in private bookings. Last year, when Switzerland’s Park Hotel Weggis launched a “Rent-a-Resort” three-day package starting at $111,000 for all 43 guest rooms, general manager Peter Kampfer expected it to be used mainly for corporate retreats. “But we are seeing that 40 percent of the bookings are from individuals—not businesses,” he says.

Sometimes business and pleasure intersect. Paula Hawes, sales manager for London’s Draycott Hotel, used to have a guest from Maui who regularly stayed at the hotel when traveling for work. She liked it so much that a few years ago she flew all her girlfriends in for her 40th birthday, reserving 20 of the 35 rooms. They had such a blast that she started inviting friends and family to London every year. But they no longer stay at the hotel. “She bought a house nearby,” says Hawes. That may be one way to guarantee the run of the place, but it’s not the only way.