How do I introduce a dog and a cat?

This works far more often than people expect, but it depends on two things being true. The cat must never be trapped, because a cat with no escape is a cat that will either fight or become permanently afraid. And the dog must never get to chase, because the chase is self-rewarding — the dog does not need to catch anything to have had a wonderful time, and that is what makes it repeat.

Safety

What you'll need

• Baby gates
• A lead and a comfortable harness
• High shelves or a cat tree
• High-value treats
• A crate or pen the dog is happy in (optional)

Step by step

1. Prepare the house before the animals ever meet.The cat needs a route around the house at height — shelves, furniture, the top of a cupboard — a room the dog can never enter, and its litter tray, food and water in that room behind a gate the cat can pass and the dog cannot. A cat that can always leave will settle; a cat that can be cornered will not.
2. Keep them completely apart for the first few days.Separate rooms, swapping bedding and blankets so each becomes familiar with the other's smell. Let each explore the other's space while the other is shut away. Nothing is gained by hurrying this part.
3. Teach the dog what to do before it meets the cat.This is the step people skip. Practise a solid 'watch me', a 'leave it' and a settle on a mat, with the cat nowhere in sight, until the dog responds reliably. Those cues are what you will use later, and they have to be fluent before there is a cat in the room.
4. First contact through a barrier only.A tall baby gate, the dog on a lead behind it. Cat free to approach or leave. The dog looks at the cat, you say nothing; the moment the dog looks away, mark it and pay generously. You are rewarding disengagement, not attention. A minute or two at a time, several times a day.
5. Watch the cat as carefully as the dog.A cat that stays, blinks slowly, sits with its tail loosely curled and eventually grooms or eats is coping. Flattened ears, dilated pupils, a low crouch, a lashing tail, a puffed tail and body, or growling means the session is over and the next one starts further away.
6. Move to the same room with the dog on a lead.Dog on a lead attached to you or a fixed point, settled on its mat, being paid for calm. The cat is never restrained and always has a route out and up. Short sessions. End them while everything is still calm rather than when something happens.
7. Refuse the chase absolutely.If the dog fixes on the cat and stiffens, interrupt before it starts — call, move away, use the lead. A dog that has successfully chased once will try again, and this is the single behaviour that determines whether this works.
8. Feed the cat somewhere the dog can never reach.Up high or behind a cat-sized gate. Dogs eating cat food, and dogs raiding litter trays, cause both conflict and gut upsets, and the litter tray in particular needs to be somewhere the cat is never disturbed at.
9. Extend the lead time over weeks, then trail the lead, then drop it.Only when the dog is consistently ignoring the cat over many sessions. A trailing lead gives you something to step on. Continue to separate them whenever you leave the house.
10. Do not leave them alone together for months.Baby gates and closed doors when you are out, for a long time after they appear fine in your presence. Many households never fully relax this, particularly with high-prey-drive breeds, and that is a reasonable permanent arrangement rather than a failure.

Tips

• A puppy and an adult cat is usually easier than an adult dog and a kitten, but a boisterous puppy can frighten a cat badly. Puppies still need the gate.
• Reward the dog for looking away from the cat, not for looking at it. It is a small distinction that changes the outcome.
• If the cat is elderly or arthritic, be more careful still — it cannot jump to safety as it once could, so its escape routes need steps rather than leaps.

Common mistakes

• Holding the cat to show it to the dog — It removes the cat's ability to leave, which is the one thing it needs. It also puts your hands and face between a dog and a frightened cat.
• Letting a first chase happen and telling the dog off afterwards — The chase itself is the reward. The dog has already learned it is fun and the telling-off is irrelevant, which is why prevention is the whole strategy.
• Not preparing the escape routes first — A cat that has been cornered once may take months to be comfortable in the house again. The environment work has to come before the introduction.
• Leaving them unsupervised too early — Everything can look fine in your presence and be entirely different in your absence. Gates and closed doors for months is the sensible default.

If it doesn't work

Questions people ask