I couldn't imagine another male here. I'm making sure my next dog is a female. One of our trainers said that female/female are generally better than male/male. She mentioned that two female dogs can bond and become the best of friends while two male dogs might only co-exist in the same house and not care for one another. I don't know if that has any truth to it but my boys seemed to have bonded quite nicely (after LOTS of fights over alpha position).