Introducing a New Dog to Your Current Dog

Most dog-to-dog introductions go wrong for the same reason: the new dog is carried through the front door into the resident dog's living room, and both dogs are asked to sort it out on the spot in a confined space with the owner tense on the other end of a lead.

The order that works

1. Meet off the property. A quiet street or park, not your yard. Two handlers, two leads, loose.
2. Walk parallel, not face to face. Start ten metres apart, same direction. Walking together is how dogs become comfortable; head-on greetings are confrontational.
3. Close the gap gradually over ten or fifteen minutes as both dogs relax. Let them sniff briefly, then move on. Three seconds, then walk. Long stiff greetings are where it tips.
4. Walk home together and enter the yard together rather than one arriving into the other's space.
5. Pick everything up first. Before they are loose together, remove all toys, chews, bowls and beds. Almost every early fight is over a resource.

The first two weeks

Feed in separate rooms, always. Supervise all interaction. Give the resident dog its normal routine, its normal spots and one-on-one time — resentment builds when the newcomer absorbs all the attention. Crate or separate when you go out, for both their sakes.

Expect a settling period of weeks, not days. Some grumbling, some telling-off from the resident dog, and some stiffness is normal communication, not aggression. Intervene when a dog cannot get away, when it goes still and silent, or when one is repeatedly pinned.

Reading the body language

Loose wagging bodies, play bows and curved approaches are good. Stiff legs, a high slow-wagging tail, hard staring, raised hackles down the whole spine, and lip curling are warnings. Break it up before it escalates by calling both away cheerfully and giving them something else to do — never by grabbing collars between two aroused dogs.

If it goes badly

Separate completely, then restart from step one over a longer timeline with a baby gate or two rooms in between, feeding on either side of the barrier. Get a behaviourist involved after a fight that draws blood rather than hoping it settles. Some combinations — two same-sex adult dogs with a history — need professional help, and there is no shame in it.