How Do I Punish My Dog?

After explaining the reward-based training approach and how beneficial it is for creating confident dogs and healthy relationships, people often wonder, "but how do I punish my dog for bad behavior? How do I let her know she did the wrong thing?"

Most of the time, when we want to use a "NO!," "Uh-uh," or "Tsk!" we're trying to stop the dog's bad behavior for good. Usually, though, it only winds up temporarily interrupting the behavior and then the dog goes right back to doing the wrong thing.

When training your dog or trying to change his bad behavior, the question is not, "how do I punish my dog's bad behavior?," but "how do I create and reward the good behavior I want?"

Although creating and rewarding your dog for the good behavior you want is a better way to train, that doesn't mean dogs are instantly perfect and always choose the good we want. How I respond to their bad choices depends on the situation:

1) Bad behavior I can't predict. Sometimes stuff happens. Years ago, I was boarding a small poodle who'd stayed with us several times before and had generally good house manners. I set my lunch on my bed and ran downstairs for a moment to get something. When I came back, most of the lunch was gone.
Once the deed has happened, there's nothing you can do about it. After-the-fact punishment doesn't work the way we want it to on dogs. If I punish her after discovering the theft, she associates the punishment with me entering the room--not with something she did 30 seconds ago. 
(In hind-sight, while her prior behavior might not have led me to predict the theft, common sense should have!)

2) Bad behavior I can predict. Rather than letting the dog repeatedly practice the bad behavior, I structure the environment so that it's very, very hard for her to do the wrong thing. Remember, practice makes permanent, and if you can predict it, you can (generally) prevent it.
For example, one of my recent boarders was a 4 month old Golden Retriever. He stayed with his housemate, a 9 year old Havanese, and another client's 5 year old Boxer. Any time I tried to put on or take off the Havenese' collar, the Golden would get all excited and bite at her tail. Obviously, she didn't take too kindly to that behavior and the whole thing made it difficult for me to get the job done.
Solution? Put the Golden behind a baby gate while I did the collar. He doesn't learn to bite tails, the Havenese isn't stressed out, and I'm able to maintain patience.
(Note. With this solution, the baby gate just pauses the Golden's behavior: it's not getting any worse, but it's also not getting any better. Should I eventually want to dispense with the baby gate, intentional training would be necessary to teach the self-control he currently lacks.)

What if I see unpredictable bad behavior about to happen? Would I punish then?
No. I verbally interrupt and then reward her for acknowledging my voice. 
A good name response, recall cue, or positive interrupter are all great options for interrupting bad behavior, but for behaviors to stop long-term, intentional training must take place.