Yes, it's important to take your dog out to relieve himself. In fact, every 5 or 6 hours during the day your puppy HAS to go. The walk is far more important than that, however. Unlike us, the dog's most powerful sense is smell. Up to 40% of their brain activity is designated for discovering and interpreting scents. Just look at the above illustration at the nasal cavity. It's gigantic! Whereas humans can only detect the most prominent smell in a room, your dog can simultaneously smell the furniture, your shampoo, what you had for lunch, what's in the garbage can, that cat that rubbed against your leg 4 hours ago, and the mud on the bottom of your shoe. When you take fido for a walk, it's like a smorgasbord for his brain. Every patch of grass is exciting to him. I would imagine it's akin to reading a good book or seeing a movie. Then he gets the added bonus of meeting other canines on the walk. Oh boy, how great is that!?! A dog's second most prominent sense is hearing. He can hear 4 times farther than you and more pitches. Trapped in your home all day, your dog gets bored. Same scents. Same sounds. Boredom leads to anxiety which leads to unwanted behaviors (i.e. ripping up shoes, compulsive grooming, excessive barking, etc) and your dog becomes unbalanced and unhappy. He needs to burn off that excess energy and pull in some new experience to his consciousness. The walk is also an opportunity for bonding with your dog. In the dog world, they don't sit around and bark at each other to relate. They move as a pack. There is something that I like to call "the zone" that happens on a long walk. Your dog gets in rhythm with your steps and both of you are silent and you begin to feel like you are moving as one unit. When I'm working with dogs, I notice a shift in their willingness to learn after we've had a walk "in the zone". This state of being is heaven to your pup. You are part of his pack. You are bonding with him. Remember, dogs interpret humans talking as excitement so silence really is key. Your being relaxed and walking with him is more positive reinforcement than you could ever imagine. You are taking him out of our artificial world of computers, t.v., loud noises, etc and bringing him back to his true habitat. The walk is also one of the best ways to establish yourself as the pack leader. The pack leader always walks in front so make sure Fifi isn't walking you. Good discipline on the walk will make all of his unwanted behaviors in the home easier to control as well. I think I could go on for days about this topic but the best way to sum it up is that dogs need to walk like fish need to swim.