1. Fear of other outside cats. Your cat may be spraying because of competition, fighting and stand offs, from another cat in the neighbourhood. They can be intimidated by cats coming through the cat flap, staring into windows or by outside cats spraying on doorsteps etc. Spray sites are likely to be near entry points, cat flaps, doors, and windows. Wash down the outside of the front/back door to clean up any smells left by neighbour cats. Put down anti-theft matting or scrumpled wire netting so neighbouring cats can’t walk so close and think about putting large plant pots as alternative spray sites further back in the garden. Also place anti theft mats/wire netting on any surface – roofs, walls etc - from which outside cats may be staring in. Use a magnetic cat flap to keep intruders out. (Staywell produce a good one). Cover the transparent part of the cat flap with Humbrol Glass Etch spray so outside cats can’t peer in. If the outside cats are troublesome at set times, close the cat flap during those times. Stick cardboard on it to show your cat that it is closed and he is safe. Take cardboard off to signal that the flap is open. Or keep the cat flap closed all the time so that your cat feels safe, and his territory is clearly defined so it doesn't need marking. This will mean supplying and litter tray and letting him in and out by the door. But the cat will feel safe. See FAQ about cat intruders for more ideas.

2. Sight/scent/sound of cats/wildlife/dogs. Sometimes a cat is spooked by the mere sight, smell or sound of neighbouring cats/foxes/dogs. Cats hate being overlooked by animals on neighbouring walls, window sills, high gardens etc. In which case the spraying will be near a window or a door which shows the sight. Block off the sight of the potential threat by covering the lower panes of the window etc using Humbrol Glass Etch spray or cardboard with masking tape. One cat was spraying on the windowsill because a neighbouring cat was jumping onto the window box and peering in. Use anti-theft mats to prevent cats sitting in overlooking areas or approaching too close to doors.

3. Fear of indoor cats. Sometimes a cat feels threatened by another cat in your household. This doesn’t mean that the cats are fighting, just that one feels under pressure, and this may be difficult for an owner to recognise. Eyeballing, ambushing, blocking pathways – these are the subtle ways cats bully each other. Spray sites are likely to be where cats have to pass each other – hallways, corridors, stairways etc. The fearful cat needs a retreat. Try putting a cat flap with a magnetic collar into the airing cupboard or similar. Also make sure there is one litter box per cat or more, Don’t just put a row of litter trays next to each other. Place them in different locations. Also have more than one bed per cat, and more than one feeding location and water location and may be more. The bullied cat must be able to get to food, water and beds without passing the bully. Install several scratching posts. Feed cats in separate locations or keep food down all the time. Reduce areas of competition. Get a cat behaviourist to come and look at their relationship and read my FAQ on inter-cat aggression. Consider rehoming either the victim or the bully. Sometimes spraying by one anxious cat makes the other anxious and it starts spraying too.

4. Too many cats. If the cat is spraying because of serious fighting within the household between cats, then you may have to consider rehoming the spraying cat. More than eight out of ten households with seven cats have a spraying problem – reduce the numbers. It looks as if the cats get on OK, but they are merely tolerating each other. When something else goes wrong, their anxiety surfaces and subtle bullying begins. Cats Protection suggests that a three bedroomed house should have only two cats. Sometimes it is the arrival of a newcomer which upsets the cat social scene. In this case, Rehome the newcomer on the grounds of last in first out.

5. New dog or some other new pet. It’s frightening for cats, that are unused to dogs, to have to live with one. Rehome the dog. Most cats are OK about rabbits, hamsters etc which after all are prey rather than predator but a very upfront house rabbit might worry them too.

6. New objects. These bring outside scents into the house. If your cat sprays on new objects, such as new furniture, Christmas tree, shopping bags etc, clean these items thoroughly and treat with Feliway. Shut away any further new items at first. Before giving the cat access, spray with Feliway or use the cotton cloth trick. Also add your own scent to the item by rubbing on or leaving or draping on a dirty T-shirt or pyjamas smelling of you! The other possibility is that the cat is spraying the carrier bags because you are putting them down on the doorstep before opening your door – and you are putting them down where outside cats spray. So clean up any area where you put carrier bags down before entering the house.

7. Building works or decorators indoors or outdoors. Very close road works. Keep the cat away from the altered rooms till paint smells etc have died down. If road works are just outside your house, keep the cat in a room furthest away. Spray Feliway or install a Feliway Diffuser in the newly decorated room or do the trick with the facial glands and a clean cloth. Consider putting the cat in a cattery if it is too awful for it.

8. Visitors. These are intruders into the cat’s home territory. Occasionally cats will spray at Christmas etc. when there are visitors. Or if a cat dislikes a visitor in the spare bedroom (previously the cat’s territory) it may spray on the door there. Sometimes visitors smell of the dogs they have left at home or there are just too many or the wrong kind (from a cat point of view). Consider using the cattery if visitors are staying.

9. Visitors with dogs. I don’t think it is fair on a cat, which is frightened of dogs, to have to bear this. Again, consider a cattery during the visit or persuade your visitors to use kennels nearby – they can take their dogs out for a walk. Or book them into a local B&B.

10. Cat sitters. Sensitive cats can be upset when left behind with sitters, when their owners are on holiday. Their core home territory feels no longer safe. The cat sitter may be seen as an intruder or the change of routine may upset the cats. Use a cattery next time.

11. Attention seeking. Occasionally spraying becomes an attention getting device. The cat will look as you as he does it. In this case you probably need expert help! Indoor cats are probably more likely to do this than outside cats. Try to give the cat other focuses for its attention, not just you – more games, install a cat flap, etc. Ask for my sheet on indoor cats.

12. New cat flap. The cat may fear intrusion by outside cats through the flap. Get rid of this or shut it down, if spraying started after installing it. Go back to what you were doing before the cat flap.

13. Electrical appliances and radiators. These may be sprayed on because when they heat up they emit odours that attract the cat. Warmed up items include radiators, kettles, cookers, toasters etc. Clean the area around. Try Feliway or the cloth trick, assuming that you can use these on a safe area of the electrical item. Do be careful of electric shocks! Repaint radiators with metal paint available from DIY (very easy). Let them dry and paint smells diffuse before letting cat have access to them.

14. Human changes. New routine, new partner, new baby. Job change if the new job makes you smell different – ie if you start working for a vet, you will smell horrible to cats.

15. Anxiety about the litter tray. Make sure the litter trays are not overlooked by outside cats or used as ambushes. If in doubt add some more in a new place. Read earlier FAQ or info sheet, “Eighteen questions to ask if your cat stops using the litter tray.”

16. Mirrors, reflections, artificial scents. Sensitive cats can be upset by their own reflection. They do not recognise themselves. Instead they think they see an intruder. Cover up the mirror. Mouse and Rat Repellers and other ultra sonic deterrent devices can badly upset cats. They are set at 30,000 to 60,000 Hz, above human hearing but well within cat hearing. Turn these off. Also turn off human scent plug ins (not Feliway). These can make the home smell wrong to a cat thus causing anxiety and making spraying more likely.

17. Hormones. Cats sometimes spray pregnant women in the first three months of pregnancy. Usually this stops later on in the pregnancy. If a companion animal – dog or cat – comes on heat the cat may also spray then. See if flooding the room with scent from a Feliway Diffuser helps or, better still, spay the animal (not the human!) on heat.

18. Medical problem in another cat. It’s just possible that a medical problem in the spraying cat’s companion cat may make it smell different and prompt spraying. So if the non-spraying cats include any oldies check for kidney disease etc. I have one case in which the companion (non-spraying) cat got kidney disease and this seems to have set off anxiety marking by its companion, possibly because the smell of the ill cat changed. Veterinary visits can make a cat smell of the clinic – a smell which all cats hate. So if one cat is coming back from the vet, the other may attack it or be frightened by its smell. Take both cats to the vet, including the well one.