People should be prepared to compromise at the park. "You may be planning to spend an hour at the dog park visiting with friends," she says. "But if you arrive and see two dogs already there who have been a problem in the past, then your plans should change and you should find another way to exercise your dog." Also, she says, people must keep their attention focused on their dog. "Even if all the dogs are perfectly lovely, accidents can happen," Smith says. "One dog can get a tooth hooked in another dog's collar and panic can ensue."

Smith warns against letting dog play get too rough.

"In good play, dogs should change positions frequently. So the dog who was being pinned to the ground should be allowed to be the dog doing the pinning," she explains. "Or the dog being chased should turn around and be the chaser. All dogs should also respect time outs. If you watch, you will frequently see a dog stop suddenly, and the other dogs in that play group should also stop."

Really rough play can easily lead to injury of either dogs or humans, she says, adding that a lady's leg was recently broken in her local dog park. Body slamming, she says, can be quite hazardous to both dogs and humans -- she knows of a dog that died after a dog park collision.

Success at the dog park is also largely about being able to read a dog's body language -- your dog and other dogs.  

For instance, Smith says if several dogs are chasing another dog, and the "victim" dog gets away and does not resume play (runs to owner or tries to hide), then the "victim" is not enjoying the interaction. If a dog gets stiff in the body, that's also an intense warning.