• Many people use guard dogs for protection.guard dog warning image by hazel proudlove from Fotolia.com
  
  Dogs are often protective, but in some breeds the protective nature is much more pronounced. For example, most dogs will bark when a stranger enters their yard or home, but a guard dog will intimidate the intruder until he retreats, or may attack. If you have an extremely protective dog, training is vital so that he will obey your commands to stand down.
  
  

Doberman Pinscher

• Doberman pinschers are extremely strong and muscular.Doberman image by Stana from Fotolia.com
  
  The Doberman pinscher originally was bred as a guard dog with the agility of a terrier. Temperament will vary from dog to dog, but you can expect a Doberman to be very loyal to his family. He won't hesitate to attack if he thinks his family is in danger.
  
  

Rottweiler

• Rottweilers have long been popular guard dogs.Rottweiler image by Stana from Fotolia.com
  
  Rottweilers are fiercely protective of their families. Added to that, the breed is known for its strength, stamina and ability to tolerate pain. What makes this dog popular is that while it's a great guard dog, it is very calm and loving to its family.
  
  

German Shepherd

• German Shepherds are famous for their protective abilities.german shepherd image by Vaida from Fotolia.com
  
  The German shepherd is one of the world's smartest dog breeds and is often used by law enforcement to sniff out drugs or missing people. German shepherds have an extremely strong protective instinct and are known for their love of children.
  
  

Giant Schnauzer

• Giant schnauzers are intensely loyal.miniature schnauzer image by Alison Bowden from Fotolia.com
  
  Giant schnauzers may not look so scary, but they are ideal guard dogs. The breed is known for being powerful and dominant, so training is essential. Giant schnauzers become very attached to their owners, so expect extreme protection.
  
  

Bullmastiff

• The mastiff's size alone can be enough to deter intruders.neapolitan mastiff image by pixelcarpenter from Fotolia.com
  
  A bullmastiff's looks help explain what makes it a good guard dog. When a bullmastiff attacks an intruder, he won't only bite, he will knock the intruder down with his large size. The dogs also have been known to stand in an intruder's way and not let him pass. This breed requires consistent training from an early age.