dog aggressive cocker

Question
I have a 3 year old cocker spaniel that I adopted from a shelter a few months ago. He is a very sweet and well-mannered dog but he does not get along well with other dogs. Some that are smaller than him, he will tolerate. Others, he will approach wagging his tail and then growl and attack. I wish we could spend time in the dog park near my house but he's just too mean to other dogs. He's been great with kids and other people but does tend to growl and bark at an occassional human (never bites them). Is there a way to help him get along with others?

Answer
Yes there is :)  Now, let's not forget his time at the shelter and how that undoubtedly exacerbated this problem.  So a little patience and some technique is needed.

First of all..never let him off leash.  Never.

What you do is "introduce" him to one dog at a time in a certain way.
You walk with your pup on one side of you - another owner walks with you with her dog on the other side with both dogs on a short leash.  Dogs are separated by two humans.
You walk (dogs don't get this way while they're in motion)...you stop briefly, ignoring both dogs.  At the first signal your dog is even thinking "bad thoughts" :) - you move on with a firm "Let's go".
Just walk & stop for 10 seconds..."let's go".

At the end of a nice, long walk you'll visibly see your dog has relaxed and pretty much accepted the other dog.  Do this for a few days and he'll have a buddy you can have over for a playdate.

Obviously you need the other dog to be a mellow, stable pup.  I've used my own cocker as a "teaching dog" this way and by day two, the boy with the problem greeted him enthusiastically.

He's not being aggressive - this is nervousness and fear.  He'll get over this if you are in control and not allowing it to happen by anticipating.  A lot of training is correcting BEFORE behavior happens.  Initially as soon as he even LOOKS at the other dog, move on quickly.  You'll see that as the walk goes on, you'll be able to stop a bit longer.

So be patient and do write again anytime.
Best of luck,
Delores