Your tail-wagging pup might love a companion dog to plot devious dog shenanigans, like how to reach the treat container on your counter, but not just any dog will do. The right companion has to mesh with your resident pup, and sometimes it all boils down to age and temperament.
Step 1
Choose a dog who has a positive temperament. Two dogs can be rough to handle if one or both are foaming at the mouth when strangers or dogs pass by, or if they tuck their tail between their legs and turn nervous or fearful when something harmless happens. You want a canine who doesn't have aggressive, fearful or overly nervous tendencies. These behaviors can make life miserable for your resident pup -- especially if he shows the same behaviors -- and they can make raising two dogs incredibly difficult.
Step 2
Know the size of dog your resident pup enjoys. Sometimes larger dogs, like German shepherds, have no idea how to deal with an ankle-high pup who's full of energy, like a Jack Russell terrier, while others romp around without a problem next to their smaller cousins. Size isn't always a deal breaker, because your resident dog will often adjust eventually, but it can make for a few rough and sometimes even dangerous weeks when you bring the new pup home.
Step 3
Pick a companion whose age won't be bothersome to your resident dog. Youngsters and middle-aged canines usually can adjust to any type of pup you bring home, but senior canines are a bit less forgiving and less willing to accommodate a high-speed puppy barking in their faces and biting at their ears. Although not a written rule, it's rarely a good idea to raise two puppies at the same time. The cute little fur balls might give you lots of "aww" moments, but hidden beneath that cute demeanor are expensive and destructive barkers who require plenty of training, socialization and playtime.
Step 4
Bring the two together for a little meet and greet. Even if you think you found the perfect companion for your resident dog, introduce the two together in a neutral place that neither dog views as his territory so they can sniff one another and get acquainted. Give plenty of treats to each dog so they immediately think the other's presence means visits from the treat fairy. If the initial introduction doesn't go as planned, don't give up yet. Try again in a day or two, but at a different location. If one or both act aggressively or try to fight, you may want to search for a new companion.
Step 5
Make sure you have separate items for both dogs. Leashes, collars and the like are obvious, but don't forget about separate food bowls, water bowls and lots of toys. You might need different grooming tools, flea and tick prevention and food for the new dog as well.
