Participation in research can provide direct and indirect benefit to individuals with autism spectrum disorder (ASD), their caregivers, families, and society at large. Unfortunately, individuals with high support needs, including those with intellectual disability, cognitive disability or minimal verbal ability, are often systematically excluded from research on ASD. This limits the ability to generalize discoveries to all people with ASD, and results in a disparity in who benefits from research. This piece outlines the importance and extent of the problem, which is part of a broader lack of inclusivity in ASD research. It also provides examples of studies that have directly addressed issues that arise when conducting inclusive research and makes recommendations for researchers to reduce disparities in research participation.