One common canine behavioral issue is fear of unfamiliar people. Some dogs are sensitive to human behaviors and appearances and may react negatively to some of them. These include a larger body, a loud, booming tone of voice, facial hair, costumes, or a hat shading the face. Dogs can interpret abrupt movements, roughhousing, or hovering over them for petting as confusing and intimidating. This fear could be caused by genetics, a lack of socialization as a puppy, or previous negative experiences. Your dog can be slowly exposed to people they are afraid of and learn to create positive associations through positive reinforcement training. If your dog’s fear is escalating to aggression, please seek professional help.