About two dozen dogs panted as they ran around a large fenced enclosure, their tails wagging as they checked each other out. Owners stood in groups or sat on lawn chairs, smiling as they watched their dogs play off-leash in a secure park.

The scene took place on a recent sunny afternoon at the South Park Dog Park and is repeated daily at other such parks in the area.

Mary Frances, of Whitehall, comes three times a week with a trio of Labrador retrievers -- Hunter and Cody, both 6 years old, and Buck, 8.

The dogs get the exercise they need, which makes them happy, and she gets to enjoy the company of the human "regulars."

"Generally, all the dogs are really good," Ms. Frances said, as she sat in a well-worn lawn chair. Although Allegheny County installed two picnic tables at the site, "people who use the park bring their old chairs and leave them here," she explained.

South Park and other dog parks in the region are most heavily used on weekends and after work hours as dog owners clamor for park settings, preferably fenced, where their dogs can run free -- safely and legally.

Although many dog owners have passionately petitioned elected officials for such off-leash dog parks, communities often resist the idea and many suburban municipal parks have signs stating, "No Dogs Allowed" -- even if they are on a leash.

But experience shows that if officials build it, dogs and their owners will come -- sometimes from great distances.

Those municipalities that do give their dog-owner residents what they want rarely extend the privilege to nonresidents. Green Tree, for example, has procedures to effectively keep nonresidents out of that town's dog park. South Fayette issues permits and only a limited number of nonresidents get them.

Dog owners, however, have a friend in Allegheny County, which allows dogs to be walked on leashes in all nine of its parks and operates leash-free dog areas in four parks: North, South, Hartwood and White Oak.

The county does not have any procedures to screen for dogs that don't live in the county.

Several neighboring counties, including Butler, Washington and Westmoreland, also have off-leash dog parks. (See accompanying list.)

Still, dog owners want more and they want them closer to their neighborhoods.

"It's frustrating," said Anthony Corcoran, who had driven from the South Side to South Park so that his yellow Labrador retriever, Sophie, 2, could have an off-leash romp. Parks in his city neighborhood ban dogs, he said, so he and his wife "drive all over" to give Sophie a free run.

"I'm a physician and my wife is a nurse anesthetist and our schedules are busy," said Dr. Corcoran, who was enjoying a rare weekday off. "I wish we had something closer to home."

Sophie is a semi-regular visitor at South Park, Hartwood and Frick Park.

Two women who had traveled separately to South Park from Whitehall also bemoaned the lack of a dog park near their neighborhoods.

Dara Gualtieri has been bringing her 11-pound rat terrier, Max, to South Park for three of his four years. Big dogs generally rule at dog parks, but Max played fearlessly and peacefully with all of the dogs, which is why Ms. Gualtieri makes the trip when her work schedule permits.

Allegheny County is pleased with the popularity of its four off-leash dog parks, said Clarence Hopson, deputy director of recreation and parks.

"We would never outlaw dogs. One of the reasons we provided dog parks is the outcry from the public" for them, he said. "All four are popular. North Park and South Park are the most popular. I feel that the more people we can bring to the parks, the better." He added that the parks "have had very few problems" since the off-leash areas opened about five years ago.

While dog parks are popular, they're not always pretty. Running dogs are hard on grass, often creating bare areas that are dusty in dry spells and muddy after rainfalls.

To address that, Allegheny County in the fall opened a different area of North Park, on Pearce Mill Road, to dogs. The original dog park on Wagner Road is closed for now to give new grass seed a chance to grow, Mr. Hopson said.

Just as farmers rotate crops to give fields a chance to recover, the county is experimenting with rotating dogs between the two North Park dog areas. Officials have not ruled out the possibility of having both dog parks open at the same time at some point.

Hours for dog parks vary but generally are dawn to dusk. Rules and directions usually are listed on the website of the governing body that runs the park.

Here's a quick visit to some municipal dog parks:

Monroeville has had a dog park in its Heritage Park, in the eastern portion of the municipality, since 2003.

The town's website has several pages of information about the park, including directions, rules and tips about how to make a dog's visit a pleasant one.

For about six years, dogs were allowed to run free in Fairview Park in South Fayette, according to Jerry Males, parks and recreation director.

"As it became more popular, it became more of a problem," he said, especially the growing number of dog owners who came from outside the community.

Most officials and residents felt that the dog run area was meant to be a privilege for residents who pay taxes to South Fayette.

In January, township commissioners took steps to limit use of the dog park by out-of-towners. Dog owners now must buy tags to use the area. Residents pay a $20 application fee and a $10 yearly fee for each dog. Nonresidents pay $50 for the application and $20 per dog per year.

Out-of-towners who sneak into the park face a $600 fine.

For every two tags purchased by residents, one nonresident tag is issued, Mr. Males said. "We have a waiting list of nonresidents."

South Fayette is not issuing any nonresident tags these days.

Officials had hoped to use the money from the tag fees to hire someone to police the park, but not enough tags have been sold to support that.

Mr. Males said the dog park has not been an unqualified success.

"We get complaints that [some people] are not controlling their dogs. One lady got her finger bit when she tried to protect her dog during an attack [from another dog]. One lady said she would never go back after her beagle was bowled over by a big dog," he said.

Cranberry opened the Rotary Dog Park in August 2008 to acclaim and financial support from the public.

"It's generally good," said Mike Diehl, director of parks and recreation. "We have had a call here and there about an aggressive dog or someone not cleaning up,'' he said.

The four-acre park was created thanks to resident volunteers who lobbied for it and raised money and the local Rotary club, which donated $45,000.

The park has a section for small dogs and two other sections for medium and large breeds. The areas for the medium and large breeds are rotated so that one area is "rested" when it becomes muddy.

Dogs are not allowed in other township parks because "it's residents' choice," Mr. Diehl said. The township conducts polls, and many people want dog-free areas, especially for the 5,000 or so youths who participate in sports, he said.

"People come from all over to use this park," Mr. Diehl said. No efforts have been made to ban or limit nonresidents, he said, because "I don't know how we would enforce that."

"It's great," John Scaglione, recreation coordinator, said of the Penn Hills Dog Park, which opened in May 2009. "Nothing but positives."

A volunteer group, Friends of the Penn Hills Dog Park, helped develop the park on Jefferson Road, off Rodi Road.

Plans include adding agility obstacles for the dogs, Mr. Scaglione said. For now, the park is open March through December because the road leading to it has not been paved yet.

Do Penn Hills officials care that nonresidents use the park?

"In a way we do, but there is no way to patrol that," he said.

About 150 dogs are signed up to play in Green Tree's dog park, which opened in the summer of 2006. The park is for residents only, and the borough website makes that very clear.

The fenced park is locked, and obtaining a key costs $20. Dogs must pass a behavior evaluation at one of the two training facilities approved by officials and must have proof of up-to-date immunizations. The key fee is refunded when the dog owner returns the key to the municipality.

Sometimes a dog park just happens.

Such is the case of a former golf course in Thornburg. The site, owned by the town, is listed on several websites for dog lovers, though one of those sites describes it as "an illegal dog park."

"That's about accurate," said Thornburg Mayor Tom Makin. He said the dog park is not sanctioned by officials and "just kind of happened."

The website that added "illegal" to the Thornburg listing did so after a borough council member contacted the website owner and asked that it be changed.

"The people who use it are not always considerate of others," Mr. Makin said. "It's a unique piece of land. It's a conservation area that we are studying for development."

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