Evidence is emerging from the Western world that, when seeking assistance, Autistic women are remaining unrecognised, or are being misdiagnosed with mental illness by the clinical professionals they approach. However, as a result of their relative invisibility there is very limited academic literature on the occurrence of the mis(sed)diagnosis of Autistic women, as these women only draw statistical interest when they eventually become formally diagnosed. This thesis provides for an exploration of this usually hidden topic. As such it is an exploratory, inductive study that is guided by a transformative worldview. I use triangulation as a methodology in the corroboration of views found to be underpinned by opposing philosophical stances. I then consider the lived experience of unrecognised autism, the clinical context of mental healthcare, and the guiding documents and reports for the provision of autism services and support for Autistic adults in the government-funded New Zealand healthcare system. This information is supported by data collected from an online questionnaire of healthcare practitioners with a specialised knowledge of autism, specifically how it presents in females. I conclude that there is a longstanding and harmful relationship between Autistic women and madness in part driven by a negative interface between psychiatric services and women in general. Issues for Autistic women are exacerbated by a lack of understanding over time of neurodevelopmental conditions within the healthcare professions that I contend could be contributing to the ongoing, and harmful phenomenon of under-recognition of Autistic women.