Significant efforts in the CHI community have focused on supporting autism research through intervention-based work. For example, applications of mobile systems, therapeutic games, gesture-based interaction, and capture and access have been studied in the context of therapy, care, and interventions for individuals with autism spectrum disorders. In this paper, we discuss how HCI can support population-focused strategies, or a public health approach, to autism research. Public health research is focused on collecting and managing large amounts of data at the population level in order to understand aspects of autism such as early detection, lifespan outcomes, and risk factors. We discuss a research agenda for HCI that involves opportunities for innovative multidisciplinary autism research at the population level rather than the individual level.