Hi, our first dallie Ben was aggressive towards other dogs apart from Domino our other dallie and was his best buddie. We used to take them both dog training and Ben was fine with all the other dogs. Why the aggressive behaviour begn we have no idea, but whenever we saw another dog it was a nightmare trying to get him to calm down. It did improve quite alot as he got older. Now, we have the same problem with Henrie, if a dog goes past our window he goes mental and barks non-stop. Again, he never used to be like it, he always wanted to play with any dog he met. If Henrie is over the in-laws and their gradson is there with his dog, henrie will play with her and then starts to get aggressive with her. I have never heard of Dalmatians being known as an aggressive breed though. Polly
