Pheromones are chemicals released naturally by dogs and cats that act as invisible communication. The pheromones are smelt by the nose and then relayed to a special device called the vomeronasal organ. From here these secret messages are deciphered by the portion of the brain that controls emotions such as fear and anxiety. By synthesizing these pheromones, we can provide stress relief cues to our pets in the form of sprays, diffusers or collars.