When Bonnie Graves retired, she told her husband she wanted to see Europe. Five months and 17 countries later, they returned to their Indianapolis home and began to figure out how they could afford to go back.

The couple joined www.HomeExchange.com, one of more than a dozen online home-swapping clubs that offer travelers a chance to stay in a fully furnished home in exchange for allowing a fellow swapper to reside in their house.

A longtime vacation tradition in Europe, the trend is beginning to catch on in the U.S., says Janice Lieberman, consumer correspondent for NBC's "Today" show and author of "Tricks of the Trade: A Consumer Survival Guide" (Dell, 1998).

Here's how it works: After paying the on-site registration fee — about $50 to $100 annually — the member lists his home and includes a preference as to where and when he'd like to vacation. For reasons of privacy, the profile does not include names, addresses or e-mail addresses, but it does list a description of the residence, usually with a photo, and the destination's nearby attractions.

While most exchanges are for one to two weeks, they can vary from a long weekend to a month, depending on availability. Although identical trade weeks are the most practical, alternative dates can be negotiated.

For example, Sherry Howell's Colorado mountain home sat dark and cold in the winter while she worked and lived in New Albany, Ind. But then she joined www.Homelink.org.

"This guy was desperately looking for a place near Breckenridge so he could ski over Christmas break," Howell said. "I had a mountain house close by sitting empty."

The would-be skier, meanwhile, had a home in the Florida Keys that he was willing to trade for a week.

The potential exchangers traded information — and then their homes.

"There were no problems," Howell says.

Of course, not every home swapper has a success story. Joelene Bergonzi and David Gross of Bloomington, Ind., listed their home with www.HomeLink.org, and Bergonzi says "although it seems impressive with all those resources, it was not worthwhile for us."

The pair tried trading out for trips to New York, Colorado and California without success.

"I tried numerous possibilities, so my experience has been that it is not easy," said Bergonzi, who paid $80 for the listing. "I don't think people understand the value of being in Bloomington, Ind., so it's not a priority to come here."