Mosby and Laila met at a dog park. So did their owners, Jenny and Matt. When a sudden shower caught Jenny far from her car, Matt boldly offered her a ride. She accepted; he was, after all, a fellow dog owner.

Two years later, Matt Barry and Jenny Taylor live in a townhouse they chose for its proximity to a dog park. They're thinking of getting married at a dog park. Together they have adopted a dog, Denver, to expand their brood.

They easily could serve as a prime example for Janet S. Owens, the Anne Arundel County executive who has taken pains to position Annapolis and its environs as a destination for dog owners.

In a county known for chocolate Labradors and, increasingly, thimble-size lawns, Owens has taken the unusual step of opening four off-leash dog parks -- and one dog beach -- on little more than a hunch that the dogs would come. She wants to market Anne Arundel as a dog-friendly county, to lure the leash-and-collar set in the same way that Blue Ribbon schools attract parents.

"This is our yard," said Taylor, 29, a systems analyst who visits the dog park at Broadneck Park in Arnold at least twice a day with Laila, a 2-year-old boxer, and Mosby and Denver, greater Swiss mountain dogs ages 5 and 2. "The only way we could live in the townhouse is knowing that this place is across the street."

The Washington region is home to at least three dozen dog parks, which typically allow dogs to run leash-free on acreage cordoned off by a fence. In the past several years, when the "off-leash" concept took off, owners who let their dogs roam free in public parks usually were breaking the law.

Dog amenities vary by jurisdiction. The District does not have a single legal dog park; legislation is pending before the D.C. Council, and until or unless it becomes law, off-leash dogs violate District code. Alexandria, at the other extreme, has 17 dog parks -- one within a mile of every home.

But dog parks often meet strenuous opposition from people without dogs who live near them: Dog poop, loud barking and loss of parkland are just a few concerns. Cities and counties seldom initiate dog parks on their own; instead, they act in response to petitions from organized groups of dog owners.

Fairfax County, for example, opened all of its five dog parks in partnership with dog owners and requires them to run the facilities. Montgomery County opened its three dog parks in collaboration with a dog owners group called MC-DOG. The seven dog parks in Arlington County all have sponsoring groups.

"The people who use them love them. And the people who live next to them generally do have some issues," said Judy Pedersen, spokeswoman for the Fairfax parks department. "There's a great fear of everything from the smells to wild dogs running loose. We've certainly had some contentious times when there have been protesters at the openings of these things."

Anne Arundel County had no dog parks until 2001, when Owens read a letter from a dog owner who had been to dog parks in California and urged her to open one here. About the same time, two Annapolis women launched a petition drive for a dog park in their city. Owens, a notorious pet lover who features a "Pet of the Week" item front and center on the county's Web site, decided to open parks in Annapolis, Arnold, Gambrills and Laurel and a dog beach in Pasadena.

"I just knew, because of the woman's letter, that it would be a gathering place for people," Owens said. "And it just struck me: It's important to building neighborhoods and community -- quality of life."

The dog park raised attendance at Quiet Waters Park in Annapolis by 20 percent in its first year; today, one car in three enters Quiet Waters to use the dog park, according to parks official John Marshall.

The county spent $20,000 on the park, mostly for fencing and a water spigot. A plastic mailbox holds wadded plastic grocery bags for poop. Owners are far more likely to be known by their dog's name than by their own.

On a recent evening at Quiet Waters, Pam Youngs arrived with a 2-year-old German shorthaired pointer named Cleo, who soon disappeared in a tangle of frolicking dogs.

Her husband brings Cleo to the park at 6:30 each morning, and she returns with him after work. They live nearby, in the Hillsmere community.

"We would not have been able to adopt her if she didn't have a place to run and exercise," Youngs said.

A short trot away lies the dog beach, an amenity that draws pet owners from miles around. Only dogs can swim there.

Lesley Bastian, a flight attendant fresh from work at Southwest Airlines on a recent evening, said she'd come just to watch other people's dogs. She has none of her own.

"I mean, everywhere you turn, you just want to giggle," she said. "They're so much more innocent than people. The little dogs, I don't think they realize they're little."

Then, she was distracted by a dripping, panting shepherd mix: "Ewww. That's so great. That's so great. Did you get all dirty?"

The popular Quiet Waters Park in Annapolis features a beach where canines are the only ones permitted to swim.