The enormous clinical and genetic heterogeneity within and between individuals diagnosed with Autism Spectrum Disorder represent significant challenges to advancing knowledge about etiological pathways and clinical outcomes. Considerable progress in this area has been made through collaborative and large-scale projects, necessitating a similarly large resource to be established in Australia. Established in 2014, the Australian Autism Biobank was initiated by the Cooperative Research Centre for Living with Autism (Autism CRC). In this presentation, I will discuss the clinical and demographic features of the 1581 children who participated in the Australian Autism Biobank, highlighting significant novel findings from the first few years, and reflecting on the challenges and lessons learned from this study. The Australian Autism Biobank is a valuable and detailed resource comprising uniquely deep clinical phenotype data alongside an array of biological samples, significantly advancing our understanding of the mechanisms associated with an autism diagnosis.