There is strong international evidence that teaching philosophy in the classroom improves educational outcomes, especially when students practice collaborative philosophical inquiry, the pedagogical approach at the heart of the Philosophy for Children (P4C) program pioneered by Lipman and his colleagues. That evidence has emerged strongly only in the past decade and a half and includes in recent years significant studies conducted in Australia. This chapter seeks to chronicle, and critique, the range of Australian research aimed at showing the impact of teaching philosophy and to identify some of the gaps in Australian P4C research.