Why some dogs lunge, bark, or fixate when they see another dog on leash, and what to do about it. Covers the pattern behind reactivity, how to manage triggers, and the approach that changes the response over time.
On-leash reactions can begin with frustration, excitement, fear, overwhelm or more than one feeling at once. Some dogs want to reach another dog but the leash prevents it. Others want distance but cannot retreat, so barking or lunging may make the dog move away. The patterns can look similar from the outside, and the behavior alone does not diagnose aggression. If your dog plants, sits or lies down across the walk rather than specifically reacting to dogs, use why dogs freeze on walks.
Threshold is shorthand for the point where your dog shifts from noticing another dog to struggling to cope. It isn't one fixed distance: it changes with the place, the other dog's movement, recent events and the day. Find enough distance for your dog to notice without exploding and still move with you. Taking food and responding are useful clues, not single tests. If your dog locks in, create more space rather than repeating cues.
When you spot another dog ahead, act before your dog locks on. Cross to the other side, step off the path, or use a hedge or hill to break the sightline. The earlier you move, the more room you have to work with. Each time the reaction doesn't run its course, the pattern gets a little less automatic.
When your dog spots another dog at a distance they can handle, still aware but not reacting, start feeding high-value treats steadily. Keep feeding while the other dog is in sight. Stop the moment the other dog disappears. Done consistently, your dog starts to connect the sight of another dog with something good, and the emotional response begins to shift.
Avoid unnecessary leash tension and never jerk the leash, but put safety first. Keep enough control to prevent your dog reaching another dog, and create distance early instead of trying to hold them close as the dog passes. A secure, well-fitted harness can protect the neck and help you move away safely.
Verbal corrections don't change the underlying association. They add stress to an already difficult moment, which can make the trigger feel more threatening over time. Closing distance faster than your dog is ready for undoes the progress you've built. If reactions are severe or you can't find a workable threshold, a qualified trainer can help you map the steps.