Robyn makes a good point. The shelter where I got Ripley actually encouraged me to bring Bella up for a "dry run" to see if they got along. Of course back at home it's always a little different, but seeing how they acted toward each other at the shelter gave me even more encouragement that things would work out at home which they did.

As for the kitty thing, I really do think a kitten might be able to blend into your household easier or a cat who has spent time around dogs before. My cats came here as kittens and there were already dogs in the house, although different dogs than the two I have now. At any rate, each introduction to a dog was very easy because the cats had been around them before and grew up with them. I think an older cat who has never been around dogs wouldn't work well, but that's just my opinion and there are exceptions to any rule.