Keeva is an extremely dominant dog, while Tango is sort of inbetween. I introduced them with Kee on a leash at first and then let them loose together after I saw that they weren't going to attack eachother or something, there was a bit of growling and snarling involved for the first few days (about a week actually) until they learned who was boss (Tango). Keeva still tests it every once in a while but they get a long just fine, you have to give it time though. I'm not sure if all people have to do this or not, but I always feed and pet Tango first and Keeva last, if I don't Kee thinks that suddenly she's in charge and that just causes major problems. So far, all of that has seemed to work with them. I hope everything goes well for you, good luck!