Viruses were recovered from throat specimens of 21 of 53 dogs with respiratory disease and from the post-mortem tissues of 7 of 10 dogs. Many of these dogs were infected with more than one agent. The agents were 2 canine adenoviruses, a canine herpes virus and a SV-5-like virus. Rises in antibody titer to the isolated viruses were demonstrated in dogs which survived. The antibody response to the SV-5-like virus was specific to the isolated virus and SV-5 and not to other members of the parainfluenza group.