At first glance, Candace Heller's back yard in Buffalo Township, Washington County, looks like a child's playground. There's a teeter-totter, a tire jump, an A-frame to climb and even a collapsible tunnel.

But this playground is for dogs.

Dog agility is a sport in which a handler is given a set amount of time to direct a dog off-leash through an obstacle course. It was originally patterned after equestrian stadium jumping, but has since evolved into a sport of its own, adding extra obstacles, scoring systems and performance standards.

Agility made its debut at Crufts Dog Show in England in 1979. It has since become one of the fastest-growing dog sports in England, Western Europe and North America.

"Everyone loves it as the dogs race around the course with tails wagging and fur flying," said Heller. Dogs compete only against dogs of similar height and ability. Handlers may give an unlimited number of commands, but may not touch either the equipment or the dog. Dogs are faulted for such things as taking down a jump bar, failing to touch highlighted "contact zones," or taking obstacles out of order.

Heller's breed of choice, the English springer spaniel, is not noted for its performance in agility, but her dogs Mari, Ellie and Star, and a rescued German shorthair pointer named Aries have all competed in agility, some holding multiple titles. Star was even on the cover of Clean Run, a national agility magazine. Heller believes in letting dogs show the handler what they want to do.

"We weren't doing too well in the conformation (show ring) and I wanted to try something fun. When I showed my dogs an agility course, they loved it and so did I," said Heller, who also breeds English springer spaniels.

Heller, with the cooperation of her husband, Cleve, has been competing in and teaching agility for about six years. "Cleve is my biggest supporter," said Heller.

Indeed, when she complained about the course at the side of their house being too hilly, Cleve set about the task of leveling the back yard and relocating the course. "It's much better and safer now," she added.

Debbie Miller-Gurchak of Peters Township appreciates the level course. She competes with 9-month-old L.S., a Shetland sheepdog she admits is obsessive-compulsive. "L.S. flies around the course with no regard to safety, either his or mine," said Miller-Gurchak. "He's a fraction too tall for the show ring, but a full measure of insanity." As if to prove his owner correct, L.S. barked incessantly as other competitors ran the course recently. "He thinks it should be his turn every time," said Miller-Gurchak.

Walt Piroth of Houston, who has been competing in agility since April with Ozzie, a 2-year old Shetland sheepdog, finds the sport exhilarating, yet complicated.

"You have to learn every obstacle by name and how to get the dog to go through it properly. Sometimes Ozzie gets a little confused," said Piroth.

"Ozzie does good. You're the one who needs work," remarked another visitor.

"Well, this isn't the easiest thing I've ever done," said Piroth good-naturedly.

Cleve Heller said training is 90 percent of the sport. "Once the handler catches on, the dog will follow," said Heller.

At first, Piroth felt a little out of place participating in an activity dominated by women.

"There are usually a couple of men at the competitions and I'll pal around with them, but after a while you get so involved  you don't even notice," he said.  "Dog people are just nice people whether they are men or women," he added.

Candace Heller says dog owners interested in participating in agility should make sure their pet is healthy.

"You don't need to have a super-smart dog, you just need a dog with a desire to please and one that is structurally sound," said Heller.  She also recommends a facility with equipment that conforms to the standards of agility competition.

"Every instructor will have different methods, but here, we use positive motivational methods: toys, lots of treats and hugs."