Hi! I'm a brand new member here, but I thought I'd pop in and share my experiences.

Last May we lost our Doberboy to Cardiomyopathy. We got him as a 9 week old pup from a very small local breeder who cared about her dogs VERY much (my motto on buying from breeders is that If I wouldn't want my own dogs living with them, then they don't get my money. She passed by my standards). As a younger dog (up 'till about 18mo), he was VERY VERY tough to have. Exceptionally high-energy, and too smart for his own good. Two hour-long running and fetching sessions per-day with numerous play sessions in between hardly kept him mellow enough to keep us from loosing our minds. He ate three couches. One quickly (when my Mom needed to go out for groceries and "didn't have the heart" to crate him), and two others slowly over the course of about 6 months. Every table leg, chair arm, and coffee table (wooden) corner was chewed up. He took about a year to be fully housebroken.

But despite all of that, he WAS the "mush" dog so many people know Dobermans as. He had a mysterious way of making even the most dog-phobic people loyal fans of his.

He was dog aggressive. Eh, well, I don't know if that's the right word for it. He never attacked another dog...When he saw one, he'd jump up in down in place and whine and bark, and snap when they got close enough. He was attacked by a Golden when he was about 20 weeks old (no big injuries - just psychological trauma), and he had been very defensive with them from then on. When given time he came to love all dogs, though.

He lived with another male dog, who was unaltered (my senior English Toy Spaniel, who is now retired from the show ring). He was never bad with him. The only time we had any trouble at all was when Storm'd inhale his food, and wander on over to Bogart's dish. Sometimes they'd have little stare-downs, and sometimes they'd growl a tiny bit. When that happened we'd just seperate them, and after dinnertime they'd be fine again.

Personally, I had FAR more trouble having two female dogs. We had a Shepherd girl (who has since passed away) with our Dachshund / Chihuahua mix, and they had many issues. Neither dog was dog-aggressive outside of the house. They couldn't be fed in the same room, and the Shepherd would snap whenever the Doxie / Chi would come near, so seperation became mandatory.

I think overall, opposite-sex pairs tend to be more peaceful, but same-sex dogs can get along in the same house, too. I know several people with even same-sex dogs of notoriously dog-aggressive breeds (pit bulls, bull terriers, etc) who haven't had any problems. It just takes some work.