I have 3 inside dogs and all 3 act different when I have the vaccuum out. Our poodle tries to bite it when it's on and chases it so we have to close her up in a room or let her out while we vaccuum. Our maltese pays no attention to it and just acts natural when it's on. Adrian our new puppy (shihtzu mix) is terrified though! so I just ask somebody to hold her or put her in a room on the bed and that way she feels safe. I don't know if she'll ever overcome her fears, but if she doesn't I'll always be there to carry her to another room where she will feel safe ;)