When researchers evaluate adult outcomes for individuals with intellectual and/or developmental disabilities (IDD), the perspective of families is not always considered. Parents of individuals with IDD (N = 198) answered an online survey about their definition of a successful transition to adulthood. Content analysis was used to describe themes and ideas present in the responses. Rather than focusing only on developmental tasks of adulthood, such as living independently, being competitively employed, and maintaining friendships, responses reflected a more varied and dynamic view of success in adulthood, taking into account the fit between the person with IDD and his or her environment. As services are developed and implemented for adults with IDD, it is important to consider the full range of goals that families have for their son or daughter's successful transition to adulthood.