The current older adult population includes a 'lost generation' of autistic people whose childhoods predated contemporary diagnostic recognition of autism spectrum disorder. Older autistic adults experience disproportionately high rates of mental health conditions and physical comorbidities, yet face profound systemic barriers to appropriate care, including late or absent diagnosis, sensory environments incompatible with their needs, and a workforce with limited knowledge of autism in later life. Access to autism assessment in later life is a matter of health equity, and provides a framework for neuroaffirming intervention, yet has previously been largely unavailable in Australian aged mental health settings. Here we describe the development of the Older Persons Autism Liaison Service (OPALS) within St Vincent's Hospital Melbourne, the first specialist services of its kind in Australia. OPALS is embedded within St Vincent’s Aged Mental Health Service, providing assessment, clinical formulation, and consultation across community and residential aged care settings. Assessment involves a semi-structured clinical interview mapped to DSM-5-TR criteria, accompanied by standardised questionnaires and complemented by an informant interview. A neuroaffirming framework underpins all service delivery, and consumer feedback is delivered through a personalised report that includes support recommendations. Capacity building activities are aimed at increasing workforce autism awareness, knowledge, and neuroaffirming care. OPALS demonstrates the feasibility and community need for specialist autism services for older adults and represents a replicable model for health services nationally. Key learnings, barriers, and directions for future research and service expansion will be discussed.