Many parents of adolescents and adults with autism spectrum disorder experience difficulty accessing appropriate services for their children, and may report low levels of parent self-efficacy. In an effort to identify the factors that contribute to the difficulties these families face, this study examined the role of demographic, systemic, and clinical need variables as they relate to parents’ experience of self-efficacy. Participants included 324 parents of individuals with autism spectrum disorder, 12–25 years of age. Results suggest that parent self-efficacy is related to a number of variables and not simply a child’s clinical situation, including child age, parent immigrant status, barriers to service access, and caregiver burden. Given the crucial role that parents often play in the lives of individuals with autism spectrum disorder across the lifespan, it is important that service providers support the efforts of parents who provide and access care for their children.