INDIANAPOLIS -- Sam and Kim Craig were newlyweds when they decided to buy a time share in Las Vegas five years ago.
Since then, they've used it exactly twice, once for just a weekend.
But they've also swapped it for weeks at Lake Tahoe and skiing at Vail, Colo. After their two children were born, the Craigs, who moved from San Jose, Calif., to Raleigh, N.C., traded it for weeks at Hilton Head, S.C., and in the North Carolina mountains.
The Craigs are among 4 million households that own time shares, a number that has more than doubled since 1990. About 1.8 million of those owners reside in the United States, where the industry has recovered from its troubled infancy in the 1970s. In all, people in 190 countries own time shares.
Much of the credit for the industry's growth goes to two exchange companies which, for the past 24 years, have helped time-share owners swap weeks they own in one place for different weeks somewhere else.
"That became the No. 1 reason people bought the product," said Ed McMullen of Orlando, Fla., a time-share developer for 21 years who helped Marriott and Hilton enter the market and now chairs the industry group American Resort Development Association.
For most travelers, the time-share industry represents the pushy salesmen who use high-pressure sales practices in an attempt to lure potential buyers.
Although 90 percent of those who sit through a sales pitch walk away without buying anything, there's the other 10 percent.
The Craigs were in that group. During one of their occasional trips to Las Vegas, a resort asked if they'd listen to a pitch for owning a week of lodging there, every year.
"They got us in the door with the free show tickets," Mrs. Craig, 36, recalled.
The Craigs, both accountants, hesitated to sign a contract, so the developer sweetened the offer with more free tickets.
The couple signed the next day, paying a one-time price of $8,000 for a week every year in a one-bedroom condominium in the Ramada Suites Grand Flamingo resort off the Strip.
Those who own a time-share interval, usually a week, and are knowledgeable and flexible can maximize its trading power and enjoy lodging at thousands of resorts worldwide for a fraction of the cost of a comparable hotel stay.
For instance, a time-share week in a two-bedroom unit in Orlando may cost $12,000, which gives the owner the right to use it for one week every year for 20 years, 30 years, or forever, depending on the deed. (Many weeks are deeded in perpetuity and are handed down to heirs).
Spread over 20 years, that's $600 a year, plus about another $400 in annual maintenance fees. Staying in comparable accommodations likely would cost twice as much.
"I like the fact that I know I'm going to take a nice vacation every year," Kim Craig said.
Time shares are available in every U.S. state and 90 nations, from sunny Caribbean resorts to busy midtown Manhattan. They range in price from $20,000 or more per week for a three-bedroom condo in high season, to as little as $6,000 for a week in a studio during the off-season.
Last year, 42 percent of the time-shares owned in the United States were exchanged, ARDA statistics show. Only 39 percent were used by the households that owned them.
The larger of the two exchange companies, Indianapolis-based Resort Condominiums International Inc., arranged 1.8 million exchanges last year, or nearly one for each of its 2.3 million members, through a network of 3,200 affiliated resorts.
The other company, Miami-based Interval International, has 850,000 members. RCI members cannot exchange through Interval, but about 50 resorts are affiliated with both companies.
"The idea of the exchange was really to fulfill that consumer need of bringing variety and flexibility to a product that otherwise would have been rather stale," said Cristel DeHaan, a former owner of RCI, which is now owned by Cendant Corp., of Stamford, Conn., the franchiser of the Ramada, Days Inn and Howard Johnson lodging brands.