The use of service dogs for children with autism spectrum disorder is a relatively new and growing assistance-dog application. The objectives of this article were to identify and describe the factors influencing an autism service dog's performance and the impact of this type of placement on the dog's welfare. A qualitative approach uses interview and observational data to characterize the dogs' behaviors and welfare with relevancy to the dogs' home environments. Identification of potential physical stressors included lack of rest or recovery time after working, unintentional maltreatment and prodding by children with autism, lack of predictability in daily routines, and insufficient opportunities for recreational activities. Results revealed that these dogs formed social relationships primarily with the parents and second with the children with autism. Failure to recognize and respond to the identified physical, emotional, and social needs can have serious impacts on the behavior, welfare, and performance of these autism service dogs, as well as parental satisfaction. As applications of service dogs expand to new domains, there is a need to assess and understand factors and variables affecting the relationship between family and service dog to ensure continued success of these programs.