Pathological demand avoidance (PDA) is contended to be a distinct presentation within autism characterised by extreme levels of anxiety in response to the demands of everyday life, manifested in excessive levels of demand avoidance. This results in complex interactions with service providers in education and health settings, impacting on outcomes for individuals and their families. This national study sought to gather the viewpoints of individuals who experience PDA, families, and practitioners, with the intention of determining levels of knowledge, recognition and understanding of PDA; exploring current pathways to assessment and diagnosis; capturing experiences of access to education and healthcare services; identifying effective intervention and support strategies; and illuminating education and health outcomes for individuals and families. This mixed-method study collates survey responses from N = 264 parents, N = 9 life partners, N = 6 individuals experiencing PDA and N = 54 practitioners, and in-depth individual and focus group interviews from these cohorts. Findings suggest that a flexible, informed and individualised approach to assessment and service provision for individuals presenting with a PDA profile is essential. Practitioners universally referred to the necessity for a streamlined, integrated and multi-disciplinary approach. The reported disconnect between education and health systems indicates a need for access to services on an equitable basis.