Most dogs will happily give up a toy to his owner or let the owner be close by when he is eating or in his bed, but some dogs will show aggression when the owner approaches him when he has something he highly values, such as a toy, a chew, or when he is eating from his food bowl or is sleeping on a favourite resting site, whether that is his own bed, your bed, or the sofa. Dogs may even act like this when someone else approaches his favourite human while he is getting a fuss! When a dog shows aggression around highly valued items, or resources, it is called resource guarding and the aggressive behaviour can include staring at the approaching person (or other animal), freezing, lip lifting (so the front teeth are exposed), snarling, air snapping, and biting. This is actually a normal dog behaviour - it is acceptable for one dog to stare at another if it approaches too close when eating a bone for example. The approaching dog should take heed of this warning and back away. Such situations only escalate into aggression if one or both dogs has not been well socialised and does not fully understand dog body language or if both dogs are equally determined to defend the object, i.e. they both value it to a similar degree and both have confidence in their ability to win any fight. However, although it is a normal behaviour, it is not acceptable behaviour to show humans as there is a risk of injury, especially if a child, who may not notice or understand a stare or lip lift, approaches the dog while it is guarding something.Resource guarding can first develop in puppies who have to compete for resources. Imagine a large litter of puppies who have to share one or two large food bowls or just a couple of toys or resting places. The more confident puppies, or ones who really value the resource will learn that showing aggression to the other puppies works to maintain access to that resource. It is only natural for these puppies to transfer that behaviour to people when homed. One mistake many puppy owners make when confronted with their new puppy growling at them over the food bowl is to take the food bowl away from the puppy, in order to teach the puppy that the owner is boss and controls the food. However, this will only confirm the puppy's fears - that the owner is indeed a threat to their resource. The puppy will likely feel even more defensive when approached again by a human but as the growling did not work on the previous occasion to keep the owner away from his food the puppy escalates the aggression to air snapping and even biting in order to get the desired response of the owner backing away and letting the puppy eat his food in peace. The same process can be applied to other resources such as comfortable resting places.Rather than confronting these puppies with threatening, aggressive behaviour, it is much better to teach them that you are not a threat. If you have just brought a new puppy home then teach him that whenever you approach the food bowl more food appears - what could be better in the eyes of a hungry puppy! Whenever you pass your puppy eating from his bowl take a few pieces of your puppy's daily ration and drop them in his bowl as you pass. Your puppy will soon learn that people are definitely no threat to their food resource. Similarly you should teach your puppy that you are not a threat to other resources such as toys and beds. It is very important to teach your puppy "leave"," drop" and "off" commands in a way that the puppy is rewarded for giving up a valuable resource rather than punished for not giving it up. This will reduce the likelihood of the puppy feeling defensive around highly valued resources. If you have an older dog with an established pattern of resource guarding then you may need to follow a behavioural modification programme. As resource guarding is a serious problem which carries the real risk of someone being injured it is highly recommended that owners seek the help from a suitably qualified behaviourist who will be able to write a tailor made treatment plan for our specific circumstances. However, any suitable treatment plan is likely to follow a desensitisation and counter-conditioning programme which starts with the dog feeling calm and relaxed, i.e. not feeling at all threatened over a resource, and then the original threat is slowly built up but so slowly that the dog does not notice the increasing intensity of the original threat. For example, start off with an empty bowl and just add a couple a small amount of food so that the dog never has enough food in its bowl to guard and therefore does not become anxious about your presence. Work at this level for a while before increasing the amount of food you add. Eventually you will be adding the dog's full meal to the bowl without him reacting at all. However, while waiting for your appointment with a behaviourist it is very important that you follow some strict guidelines to prevent anyone being bitten. When feeding your dog, shut him out of the room while you prepare his food. Only let the dog back into the room once you have put his bowl on the ground and then leave the room taking anyone else with you. Do not allow anyone else back into the room until your dog has had time to finish eating, check this is the case before approaching the dog or letting any children back into the room. If you need to move your dog off a piece of furniture or make him drop an object use indirect distraction, such as running from the room in an excited manner - your dog is likely to stop what he is doing and follow you to see what all the fuss is about. This allows you to shut the door to the bedroom or living room where he has been resting or retrieve the object he has dropped. Otherwise avoid approaching your dog in situations where you know he has shown aggression before and ask your vet to refer you to a behaviourist. By following these guidelines your dog is less likely to show guarding behaviour and is therefore less likely to injure someone while you await professional help.