I currently have several clients with dogs with severe cases of fearfulness. The fear is expressed with reactivity to dogs, people and things resulting in withdrawal and or aggression. These are challenging cases and very stressful for the dog’s owner. Progress is often slow and requires behavior modification, alternative interventions as well as pharmacological treatment by a veterinarian. Often the dogs anxiety can be explained by poor socialization, abuse and neglect however fear can manifest itself in dogs without traumatic histories. This article explores maternal transmission of fear in humans that may explain why some puppies inherit anxiety and the behaviors that go with it.