Helen Goodrich of Silver Spring had a four-bedroom house and no one to share it with. A phone call and an interview later, she had a house mate and someone she could rely on to help defray the cost of her mortgage by $250 a month.

Operation Match had done it again.

The home-sharing program, which has made 1,000 such arrangements in Montgomery County in seven years -- celebrated its successes Tuesday with a party at the Rockville Civic Center Mansion. Invited were dozens of homeowners and tenants who had been matched by the program.

"It works out great," said Goodrich, who has rented the downstairs of her home to two tenants in the past several years. "It's like anything else. You get the right person and it works out."

Operation Match was originally begun as a resource for elderly homeowners to share their homes with other elderly people who needed an affordable place to live in high-cost Montgomery County.

But soon after its inception, the program was expanded to include renters of all age groups.

Many Montgomery County renters just can't afford apartments, which rent for an average of $400 a month in the county, program organizers said.

"The need for the program is so crying in this area," said housing counselor Marilyn Wisoff. "We get calls from college students, summer interns, mature people, sometimes people who need places to stay for five days a week. We're a clearinghouse for people who need housing."

The clearinghouse works like this: People who need housing and people who want to share housing fill out applications with the Housing Opportunities Commission of Montgomery County.

References are checked by counselors and interviews are conducted with prospective tenants and homeowners.

Eventually, if all works out, the right homeowner is matched with the right tenant.

The housing arrangement can include sharing rent, sharing utility costs, or even exchanging room and board for household help.

The parties involved work out the arrangements, and there's no cost for the service.

"It saves the homeowner and the person looking for a place a lot of time," Wisoff said.

The first time Goodrich opened her home to a stranger, she found a friend. The renter, who recently moved to another apartment, still comes back to visit.

"I hate living alone," Goodrich said. "It's not that I want a best friend. But I like having someone else in the house."

Since the Montgomery program began years ago, similar housing services have begun in Prince George's, Arlington and Fairfax counties and in Alexandria and Falls Church.

The success rate of the matches is high, said Wisoff, and often leads homeowners to use the service a number of times.

"When there is a problem, we tell them to use their common sense. They can always say 'Will you please leave?' . . . . But most of the matches kind of live their natural lives. They end quite nicely," Wisoff said.