My wife and I have been searching for a good companion dog for awhile. We visit the shelters because . . . well . . . there are good finds to be had.

Which is what we thought we had in this dog. She's a spayed rottie who appears to be roughly 3-4 yrs old. Led her from her pen past a bunch of other dogs in their pens, and no signs of aggression appeared. Took her for a walk, and she was the sweetest, most attentive dog we'd yet seen.

Get her home, and our neighbor dog is barking at her through the fence. Nothing from our rottie.

Next day, we take her for a walk in the park, where we encounter several other dogs. Like Jekyl and Hyde. Dear lord, she lost her mind.

We have driven by dogs, with her in the back . . . window down just enoughg for her to poke her head out. She attempted to climb out the window.

Aside from this, she shows ZERO aggression. My two year old daughter can interrupt her feeding with water dish play, and all she does is back away from the bowl. She demonstrates the usual "keep away" tendency with her ball, but will not fight to keep it when reached for.

I've since purchased a prong collar to start handing out corrections as we meet other dogs on the street.

Is there anything else I need to start doing?

If taking the dog back to the shelter is not an option, then I would suggest you take a look at the articles and the Q & A on this site.

I would definitely read the Leerburg articles and the posts on this. I have a dog aggressive dog and its source is fear aggression -- and a fear aggressive dog is different than one with dominance......

If you can't tell the difference, I would find a good trainer in your area ---- I did not know what i was doing several years ago and did more harm than good with a pinch (my post is one with a still unresolved outcome).....

http://www.leerburg.com/cgi-bin/UBB/ultimatebb.cgi?ubb=get_topic;f=18;t=000062

If you do it right and follow the instructions you can manage this problem in most dogs.

She seems to be ok,at home and off leash. But on leash in a new enviroment, she seems to go into a protection mode. Do you get anty or excited when the other dogs approach inticipating an encounter.
As mentioned sometimes the dog pickup your feelings and is reacting in a protective/aggressive manner.

You seem to be handling it ok, with sit and the "No". I'd pop the leash a little at the first sign of aggression and place her in a sit and praise her while in the sit as long as she was under control, raise your finger in front of your face to place her attention on you, then praise.
Or pull out a chew toy for same reason.

Timing is important there is some fear that the dog may think you are praising her aggression if your timing is off. This is just MO, I'm not a pro trainer. <img src="/ubbthreads/images/graemlins/cool.gif" alt="" />

Yeah, I read the thread posted above, and play to put them into action (we didn't get out for our walk last night). This incident happened with her ON leash, at home. Thanks for all the responses!! =)