Sophia A. Yin is a Davis, CA veterinarian, author and lecturer, with a specialty in animal behavior. She's the former pet columnist for the San Francisco Chronicle, and lecturer at UC Davis. She has written books and made over 50 training videos. She helps owners experiencing problem behaviors with their pets and works closely with veterinarians and veterinary technicians teaching how to interpret animal body language and ways to lower the stress involved for pets during visits to their veterinarian. Dr. Yin is a proponent of positive reinforcement training and has developed a remote controlled device to aid in the training of pets at a distance.