Current research indicates that young children are capable of developing mathematical concepts and reasoning much earlier than previously considered. Moderated by Professor Collette Tayler, this symposium on assessing young children's literacy and mathematics understandings is in three parts. Firstly the authors explore the Pattern and Structure Assessment (PASA). PASA is an early mathematical assessment interview which focuses on a range of concepts and processes and is linked with mathematical attainment in the ACER Progressive Achievement Tests in Maths (PATMaths). Secondly, the authors report on the piloting of an early-years technology-based tool called the Digital Early Reading and Mathematics Assessment (DERMA). DERMA is an audio-based assessment of early reading and mathematics skills delivered on offline tablets fitted with headphones. Finally the authors discuss the Longitudinal Literacy and Numeracy Study (LLANS) Transition from Preschool to School. This study has investigated literacy development of preschool children from preschool to Year 1.