Protect your dog from becoming aggressive by knowing where he is and who his playmates are. The topic of leash aggression arises so often, I feel the need to address it often in my blogs. For dog trainers it is very clear why we do not let our dogs greet unknown dogs while on leash. I want my dogs attention on me when I have him on a leash. I prefer he not pull my shoulder off when on leash, so I never let him greet other dogs when on leash and guess what? He does not ask anymore because he knows the rule structure. In my opinion, the BEST reason to avoid letting your dog greet unknown dogs while on leash is to keep him or her safe. Once your dog gets into a scuffle while on leash, just the site of a dog while on leash can become very scary for your pup.
We have all seen or heard stories of two dogs greeting on leash and it ends badly. Let’s think about it, when dogs greet off-leash they are able to circle, sniff and have the freedom to move away if one dog becomes stiff, defensive or worried. When on-leash we often tighten the leash, which makes the dog feel trapped because it cannot flee the environment. As a result, the constrained dog may send the other dog a distance cue like a hard eyed stare, a lip curl or a low growl. Depending on the social skills of the other dog, this may turn into an unwanted scuffle. If you want your dog to have good social skills and avoid aggression, let him have an opportunity to socialize and play with other GOOD dogs. Start with an AKC STAR Puppy class, teach your dog leash manners throughout his adolescence and set up off-leash playdates with dog-friendly dogs that you know he enjoys playing with and who have owners that you are comfortable with.
A large part of my business is helping dog owners understand why their dog is jumping and snarling when on a leash in the presence of another dog. This behavior is done by your dog for a variety of reasons. He may have learned that it keeps him/her safe. Dogs that have been traumatized by another dog, or multiple dogs, learn that their best defense is a good offense. If this behavior works for them, why would they need to change? Being safe simply feels good.
I do understand your dog needs daily exercise to get him through his adolescence. If your dog plays well with the neighbors dog, then your dog is already social! Walking on-leash together is a great way to learn leash manners around other dogs. Or, hire a dog-walker who only brings one dog to your session and watch how your dog interacts with that dog. Your dog-walker will help him learn leash manners and prevent any unwanted behaviors from being reinforced. Many dogs are surrendered because they can no longer cope with being on a leash in society. Who’s to blame? These dogs were not born dog-aggressive. Rather, it is learned by putting them in environments that are out of control and scary. So please know who your dog is playing with, and if the play is appropriate. We can all agree that aggression breeds more aggression, so please know who your dog’s friends are!
In the photo to the right, my Outdoor Adventure Class is open to dog friendly dogs. Dogs that have good emotional control, dogs that can sit and 
watch a dog go by without demanding to get to it, and dogs that are not overly pushy. If your dog is demanding to say “hello” to every dog that goes by, think about why that behavior is developing and where it is being reinforced. I hope to see you and your dog in a training class, while on-leash and enjoying each other’s calm company!