Guide · UK · checked 3 October 2026

Adding a second dog: go slowly.

Dogs in the same home do not always become friends, and some never do. The charity Dogs Trust has published a step-by-step approach to introductions. This is our summary of it, for people thinking about getting another dog.

This covers introducing a new dog to a dog you already have. It does not cover cats, other pets or children. It is general advice from one charity, not a guarantee that two dogs will get on; ask a qualified behaviourist or trainer about your own dogs.

Before you choose

Each dog is an individual, and some prefer their own space. Dogs Trust says an elderly dog, for example, may not welcome a bouncy puppy. It suggests talking to a qualified behaviourist or trainer before you start looking, to work out what kind of dog would suit your household.
Check that every dog’s vaccinations are up to date before they meet. A puppy stays vulnerable to infection from other dogs until at least a week after finishing its vaccination course.
Dogs Trust says its rehoming centres arrange for the whole family, including current dogs, to meet the dog first; if you are adopting elsewhere, ask whether they do the same. If you are buying from a private seller, Dogs Trust suggests asking whether the dogs can meet on neutral ground before you commit.

Preparing the home

Let the dogs get to know each other’s scent first, for example by swapping a blanket or toy and letting each dog investigate it at its own pace.
If your current dog’s bowls or bed will move, move them a few days ahead. On arrival day, put away your current dog’s toys, bedding and bowls for a while to avoid competition, then give each dog separate places to eat, drink and rest once the first hours have passed.

The first meeting

Meet somewhere outside the home, such as a quiet park, with a helper so each dog has its own person and both are on lead.
Walk the dogs separately at a distance, keeping each one’s attention on its person, and reward calm behaviour.
Move gradually closer once they have settled.
If both seem relaxed, let them greet briefly on lead, then keep moving; repeat if they are comfortable.
If either dog seems uncomfortable, move away and give space. You can spread introductions over days or weeks.

For a puppy, Dogs Trust says to meet in a place with little dog traffic, and only once it has been at least a week since the puppy’s first vaccinations.

The first days and weeks

Go indoors via a neutral area such as the garden, with indoor leads or house lines on both dogs so you can separate them. Avoid narrow spaces and your current dog’s feeding area.
Supervise their time together for the first days and weeks, keeping both dogs on leads or house lines; when you cannot supervise, keep them in separate rooms. Give both dogs regular breaks from each other.
Puppies are still learning social skills and need extra supervision and support.

If tension builds

Mild signs of discomfort include walking away, turning the head away or lip-licking. Dogs Trust suggests calling one dog away or sending each to its own bed to make space.
If either dog barks, lunges or snaps, separate them straight away and give them time apart, which may be hours or days. See a vet if either is hurt.
Dogs Trust advises seeing an accredited trainer or behaviourist before trying again. Dogs Trust notes that growling is a warning that a dog wants space.

Read it at the source

Dogs Trust: introducing a new puppy or dog to your dog ↗

Planning to add a dog? Our finder has an “Another dog” option that adds a reminder to plan gradual introductions, and every profile lists questions to investigate.

Limits: one charity’s advice; we have not reviewed the evidence behind it. Following it does not guarantee the dogs will get on.