[Ringo1]

I took my Westie to a trainer because he was so aggressive to other dogs (usually big ones) on a walk.

His methods were somewjat less than positive and probably made him worse.

Here is what worked for him: first I used the 'watch me' technique. Hold a treat up to your face and say 'watch me'. When your dog turns and gives you his attention and is, in fact, 'watching you' then give him a treat. Do this a few times until he knows the 'watch me' command.

Then start using it in a walk; when another dog approaches and your starts going crazy -use the 'watch me' command. Hopefully, he will realize a yummy treat is coming his way and give YOU his attention instead of the approaching dog. Then treat him.

Eventually, he will come to associate an approaching dog with something good - like a treat and he will no longer spend all his time barking and carrying on.

This took a long time and still requires that I remain focused on our walks. When I see another dog approaching and sense that Ringo is about to go off; I put him at a heel. I no longer need to take treats with me - but I still have to be focused otherwise, he will go off on the approaching dog.

This is definitely something you can work on and improve.