If you have been through a traumatic event or live in a shady neighborhood with lots of crime, getting a guard dog is a responsible option. Good guard dogs do not necessarily have to be vicious little monsters that you cannot even get near though. The best guard dogs are dogs who love you and only you.
Be aware that good guard dogs are often not good dogs if you have a lot of company. Good guard dogs will often be loud and occasionally vicious to new people.
The german shepard, like the two dogs below are go to guard dogs. The german shepard is not outwardly vicious but they can get standoffish to strangers. If you want a german shepard to be friendly with certain people, be sure to introduce them early. The longer they spend with a person, the more they will bond with them and act friendly.
German shepards are revered for they extreme loyalty and protective nature. Getting a german shepard to bond with you after they have grown up from a puppy is more difficult than other dogs. They take a while to trust, but when they do trust you they will protect you to the death.
German shepards can also be a little overprotective. I have seen german shepards start growling when their owner gets hugged or touched by another person. However when there are no strangers around, they are just big sweethearts.
Doberman's are perhaps the most feared of all the guard dog breeds. Thier name even suggests they should be feared as 'pinscher' is german for 'biter'. This breed, if not properly trained can be hard to manage. They can be hard to train for an amateur dog owner because they respond well to positive reinforcement and respond terribly to negative reinforcement. Many amateur dog owns think negative reinforcement is the only way to go, so thus this breed will be unmanageable. If you are not willing to put the work in, you may want to consider a breed that is easier to train.
Once doberman's are trained, they are just as lovable as any other dog. They do, unlike some other guard dogs, need almost constant attention. Be sure to have room for your doberman to sleep next to you as it will want to be a constant companion.
They also require a lot of exercise to maintain their sleek frame. Like other guard dog breeds, the doberman is also fiercely protective. they are very suspicious of strangers, often staying in a room and watching them quietly. It is possible this is why people are so unnerved by them.
Rottweilers are another classic guard dog breed and for good reason. Unlike other dogs who will run along the fence and back at strangers, the rottweiler will often just stand it's ground and stare the stranger down. This scares most people off. Even seeing a rottweiler in the yard will scare off most burglars.
These dogs, surprisingly, are from herding stock. While they will not heard people around like a border collie or german shepard will, they still love agility activities like frisbee or fetch. The rottweiler has tons of energy so be prepared to keep up with them.
Rottweilers as more independent than the doberman or german shepard, but they do still crave some attention. They like to play more than they like to cuddle though. A rottweiler appreciates a confident owner though, more so than any other dog. If needs an owner that can take charge over it or else you will have discipline problems. If you train them poorly, a rottweilers' favorite activity is to chew on your shoes.
If you visit a dog park that actually allows this breed, be sure to keep them on a leash. Rottweilers do not like other dogs at all.
The boerboel is probably a dog you have never heard of. The boerboel originated from a mastiff being taken to South Africa and mating with other large dogs. Eventually this mutt evolved into its own breed. The boerboel is an excellent guard dog for people who do not need a serious guard dog, but still want a breed that can protect them.
The boerboel is not an outwardly aggressive dog. It is quite loving to it's family and can be just as loving to strangers that are introduced to it. Strangers it finds on its own though, the boerboel is not so fond of.
The boerboel is very protective of its family and house and because of its large size often deters anyone prowling around your house. The boerboels' bark is bigger than its bark though. They are really quite sweet and playful creatures. Because of its large size though, it does not do well in small homes. You should find another breed unless you have a backyard for this big baby to play in.
This is really more of a bonus dog. The wolf dog is half wolf and half some other large guard dog. people say these are not often good pets because their wolf instincts are still quite strong in them. However if you get your wolfdog as a pup and treat it with love, they will be just as sweet as other dogs. They eat a whole bunch though. A wolfdog is most commonly bred between a wolf and a german shepard. The german shepard gives them a fiercely protective nature, but the wolf in them beckons them to be more independent than most guard dogs.
They can be as vicious as a wolf when confronted with something it sees as a threat or when it feels its family is threatened.
Because the wolf genes that dictate looks are often dominate, these breeds come out looking almost exactly like wolves.
Anyone who sees what they think is a wolf prowling around your yard, they are sure to stay away. Most people view these mutts as somehow evil, but they are as loveable as any dog.