All dog breeds, shapes and ages react differently to people, other animals and a change to their environment. Some dogs love other animals while some react differently to each dog. The way your dog reacts to a new dog at the park versus in the home can be like night & day.
Those of us that foster and rescue know the importance of a proper introduction. It could make or break the new dogs future. Most rescued dogs have a questionable history that is more than likely completely unknown, making it even more important to make each dog relaxed and prepared.
Dogs display body language as part of their communication amongst each other. Being on neutral territory for the fist meeting is key. Meet the new addition outside your yard on the roadway. Have a friend lead your dog and you lead the new dog. Do not allow them to come within 3 feet of each other in the beginning. Start walking the dogs just as if it was your everyday walk except walk on opposite sides of the road. They can get familiar with each others body language while burning off the built up energy/anxiety. Depending on both dogs behavior, slowly start walking closer together until they have touched each other and had a proper "hello" which is face to face but quickly moving into an "s" curve which is side by side facing opposite directions, sniffing each others rear ends among other things! It may take more than one walk, that method may not work or the dogs may be incompatible. You are almost certainly setting the dogs up for problems without a neutral and relaxed introduction.
