A dog that pulls on the leash can spoil more than a nice walk, and Emily Pelecanos of Silver Spring, Md., has the photos from her 50th birthday party to prove it.

Her husband had ordered a limo to take them downtown to a fancy restaurant - but of course, first the dogs needed to be walked. While she chatted with a neighbor, her dog, Buster, saw a dog that she didn't see coming — and he lunged for it.

"I hit the pavement with my hands and my face," she recalls.

Determined not to cancel the party, Pelecanos iced the emerging bruises. "Then I put makeup on and big sunglasses," she says, "but you should have seen everyone in the restaurant whispering."

Even if your pulling dog doesn't stop a party, the problem can be a vicious circle. A dog that's difficult to walk gets walked less, so he doesn't get enough exercise and socialization. Then he becomes more excitable and difficult on each walk.

There are a number of special harnesses and halters that are designed to solve the leash-pulling problem. (Don't confuse these with regular harnesses, which actually make pulling easier: There's a reason that dogs are attached to a sled with a harness instead of by their collars.)

But even if a no-pull harness helps, it's best not to rely on it as a permanent solution, if for no other reason than that it may not last. For Buster, a front-attaching-style harness worked — until he grew bigger and more accustomed to it.

So trainers recommend that you view these products as a tool that allows you to give your dog enough exercise and exposure to new situations that he'll be able to concentrate on training.

To start training your dog not to pull, first, recognize that lunging in reaction to something exciting, like Buster did, and constantly walking at the end of a taut leash are different problems. Some dogs do both, and owners may describe both as "pulling."

For a dog that lunges, try what trainers call "training an incompatible behavior." The idea is simple: "Instead of lunging at the bicyclist, you sit and get a treat," says trainer Victoria Stilwell of "It's Me or the Dog" on Animal Planet.

Make sure your dog can reliably sit for a treat at home. Then, start by having him sit for a treat on walks when nothing is happening to distract him.

Next, when you see an exciting dog or squirrel before he does, get him to sit and keep sitting as the distraction passes by. Most dogs catch onto this quickly, especially for a desirable treat.

If you don't react in time to get a sit before your dog lunges, it's best not to ask him to sit afterwards; it's easy to accidentally train the dog that lunging and then sitting is what gets him a reward. But do your best to prevent the lunge in the first place, because it's "self-reinforcing" — that is, it's so rewarding to the dog that it easily becomes a habit.

If your problem is a dog that's always dragging you down the street, try what behaviorist Emily Weiss calls the "red light" method: "When the dog hits the end of the leash, you stop. When the dog relaxes and there's slack in the leash, you start walking."

As Stilwell says, the basic idea is "teach the dog that it doesn't get to where it wants to go when pulling." And remember that you're not teaching him to heel at your side, which is different, and much harder. He can walk ahead of you, as long as the leash is loose.

Make sure to do this training when the dog is fairly well exercised, so he's worked off enough energy to concentrate — that's what your no-pull harness can help with.

With enough patience, your dog will catch on. "You're going to look silly when you're walking down the street, and it can take a while," says Weiss, "but your dog will eventually learn the connection."