PURPOSE:Companion dogs can provide psychosocial benefits for their owners. Assistance dogs reportedly provide similar benefits, while also performing specific tasks. These psychosocial benefits may increase their handler's quality of life and ability to thrive - defined as having the ability to grow and flourish, especially in the face of adversity. Currently, no studies compare assistance dogs' effectiveness to companion dogs' in assisting their handler/owner to thrive, an important comparison given that companion dogs are typically less expensive to acquire, and more readily available. METHODS: The Thriving Through Relationships (TTR) theory was used to inform the development of a human-dog relationship survey, which was distributed through assistance dog organizations and to the general public. RESULTS: Participants were divided into three groups: persons with a disability who had an assistance dog (n = 165), persons with a disability who had a companion dog (n = 249) and persons with no disability who had a companion dog (n = 198). Perceived overall support was statistically different between the three groups, F (2, 394) = 14.45, p < .001. Assistance dog handlers reported receiving significantly higher levels of support than companion dog owners with disabilities (p < .01) or without disabilities (p < .001). In fact, assistance dogs were reported to provide more support (p < .017) than companion dogs on nine out of ten separate indicators of thriving. CONCLUSION: Overall, dogs are perceived to provide support that improves their handler/owner's ability to thrive. Most importantly, however, assistance dogs may provide greater support than companion dogs for persons with a disability and, therefore, may be worth the additional time and financial cost. Implications for Rehabilitation Assistance dogs could assist rehabilitation by improving coping skills, especially during times of adversity, as demonstrated through the ten indicators of thriving. Assistance dogs and companion dogs are not inter-changeable when it comes to providing support for individuals with a disability.