If there's one thing dogs and humans have in common, it's that you won't find a member of either group who's perfect. And think about it: you wouldn't want to. Consider your favorite people--part of what renders them so endearing are their quirks, complexities, and funny habits. The same goes for your pets; their idiosyncrasies are what make them lovable and unique.

That said, you do want your dog to be a well-behaved, self-assured, and respectful member of the family. Setting expectations and establishing clear communication helps ensure a truly happy coexistence.

Many canine misbehaviors are born out of instinct, and most arise from either boredom or stress. Aggressive behavior, chasing, marking, and resource guarding are modern manifestations of dogs' early instincts to acquire food and protect their territory and pack. Digging and chewing, on the other hand, are usually the results of boredom. Barking is a little of both. Jumping up and mouthing are simply examples of one species (dogs) attempting to make a connection using very different forms of communication than another species (humankind) understands.

It's important to recognize that these behaviors are innate. When your pup digs up your flowerbeds, he's not seeking revenge or trying to punish you for taking away his tennis ball. Dogs simply aren't programmed that way. But for him to learn what is and isn't appropriate in the world you share, you must act as the benevolent leader of your household:

• Set boundaries and be consistent.
• Reinforce good behavior with plenty of treats, toys, and attention.
• Ignore unwanted behavior as much as possible.
• Make sure your dog knows he's a beloved and important part of the pack.

Note: Any behavior can be made much worse by inadequate training or poor handling. Physical force is never effective and only weakens the bond you're trying to build.

Preventing bad behavior

Preventing a bad behavior is always preferable to having to treat it, and early training is key. Enroll your puppy in obedience classes and practice with him daily, even after the course ends. Training not only teaches your dog mannerly and useful behaviors ("sit," down," etc.), it hones impulse control and provides essential mental stimulation. It's a good idea to add to his repertoire of tricks and skills throughout his life.

Early socialization is the other key ingredient. Before he reaches 12 weeks of age (when the window of opportunity begins to close and dogs start fearing the unfamiliar), expose your pup to as much as possible.

Introduce him to people of all shapes, sizes, and colors, young and old, male and female. Arrange for playdates with dogs of different breeds, maturity levels, and play styles so that he learns good canine manners and play behavior. Finally, acquaint him with a wide variety of sights and sounds, from kids riding skateboards to the toilet flushing to Fourth of July fireworks.

Treating behavior problems

Some of the most loving, loyal, and intelligent dogs come from shelters where the majority are well past 12 weeks of age. If you've missed that window of opportunity for socialization, or a particular behavior already exists, treatment can be very effective.

Providing your dog plenty of mental and physical exercise is crucial to maintaining a well-adjusted dog (it's also an effective prevention tool). It's true: A tired dog is a happy dog, and the more physical and mental stimulation your dog gets, the less likely he'll be to dig, chew, or escape.

Like humans, dogs are social animals. Making him spend long days alone with nothing to do is not only cruel, it's an invitation for bad behavior. In the absence of being given something to do, your dog will create his own ways to amuse himself. If you work all day or are gone for long stretches, consider hiring a dog walker or finding a doggie day care.

For serious issues such as separation anxiety and aggressive behavior, consult a reputable trainer or behaviorist. In those cases, desensitization is usually the preferred method of treatment. Essentially, desensitization pairs positive reinforcement (treats, praise, attention) with whatever triggers the bad behavior, thereby creating a new, positive association with the trigger.

In plain English: Your dog barks and lunges (anxious behavior) whenever the neighbor kids whiz by on their bicycles (trigger). Solution: Starting with very limited exposure, pair the sight of kids riding bicycles with plenty of treats and praise (positive reinforcement).

Bottom line: Canine misbehavior is rooted in instinct and intensifies when a dog is bored, stressed, or both. Early training, mental and physical exercise, and plenty of attention go a long way toward both preventing and treating behavior problems. Some cases require the help of a reputable trainer. Physical correction is never appropriate and nearly always makes things worse.