Low-income and ethnic minority families continue to face critical disparities in access to diagnostic and treatment services for neurodevelopmental conditions, such as autism spectrum disorder and attention deficit hyperactivity disorder. Despite the growing cultural diversity of the United States, ethnic minority children and families continue to be substantially underrepresented across research on neurodevelopmental disorders, and there is a particularly concerning lack of research on the treatment of these conditions in low-income and ethnic minority communities. Of note, there are currently no published studies on adapting autism spectrum disorder treatment for low-income Latino communities and relatively few studies documenting adapted treatments for children with attention deficit hyperactivity disorder in these communities. This article describes methodological considerations and adaptations made to research procedures using a Diffusion of Innovation framework in order to effectively recruit and engage low-income, ethnic minority, particularly Latino, families of children with neurodevelopmental disorders, in a comparative effectiveness trial of two school-based interventions for executive dysfunction.