Autism Spectrum Disorders (ASD) is generally characterized as a developmental disability of unknown cause (potentially a combination of environmental, biological, and genetic risks) and with no sure cure or treatment. ASD is a divisive issue that has inspired the emergence of different movement groups of which the two major ones are the neurodiversity and alternative biomedical movements. Neurodiversity and alternative biomedical movement groups both challenge how researchers and medical professionals think about and approach ASD. The neurodiversity movement is primarily comprised of autistic self-advocating adults who argue that ASD is a brain difference, as opposed to disorder. Framing ASD as a social and cultural issue, neurodiversity advocates demand recognition, acceptance, and accommodation. The alternative biomedical movement, however, is dominated by parents of children with ASD. Alternative biomedical advocates contend that the condition is an immunological disorder triggered by environmental toxins, from which children can be recovered through various combinations of dietary changes, supplements, and alternative therapies (e.g., hyperbaric oxygen therapy, helminths, and ionic detoxification foot baths). This research studies neurodiversity and alternative biomedical advocates, to better understand how experiences with ASD influence health social movement participation, shape beliefs about ASD, and orient challenges against the dominant paradigm. This study seeks to understand how advocates of these two groups experience, think about, and subsequently, approach ASD. The project will also offer insights into issues important to the improvement of social and healthcare services for autistic adults (such as access to safe housing, employment, and support services), and to understanding immunization non-participation and alternative medicine use in ASD-related care. This study focuses on three areas of inquiry: experiences with a medicalized condition, knowledge and expertise, and health social movements. Extant sociological literature on experience of illness often privileges the perspectives of "sick" or suffering individuals, but have under-explored (i) caretakers with highly involved and indefinite commitments to "sick" individuals and (ii) diagnosed individuals who reject their medicalized statuses. Comparing neurodiversity and alternative biomedical advocates' pluralistic experiences with ASD enables deeper understanding of movement identification, ASD beliefs, and movement goals. Furthermore, the researchers will examine the processes through which movement groups and advocates develop their own specialized knowledge on ASD. This knowledge can compete with and challenge mainstream paradigms, therefore the researchers will identify the strategies advocates employ to expand and preserve neurodiversity and alternative biomedical fields of expertise. The study implements qualitative methods that will include observations of neurodiversity and alternative biomedical events, in-depth interviews with advocates, and textual analysis of materials issued by and written about the movement groups. These research methodologies aim to address the following questions: How do advocates come to participate in and adopt movement agendas? How do movement advocates frame their opposition against mainstream scientists and medical professionals? And, within their movement groups, how do advocates generate knowledge about ASD?