What great progress now that he can actually play with a dog without being aggressive. Like the others before me I hate any sort of training aid which hurts the dog such as a pronged collar.

I believe in positive re-enforcement, louds of praise & treats when good & ignore the bad times. yes dogs are less agressive OFF the lead, when on a lead they can't get away from the other dog/dogs so the only thing to do is to act aggressivly, plus if you yourself act nervous and pull him back, holding him tightly etc he thinks it's something bad to sniff at another dog.

Sasha is off the lead as much as poss, we play "fetch" with her all the time and she often ignores other dogs around her, she chooses her friends that way - as we do!

Just keep on with what you are doing - you are getting there.

Chris