From 11 to 13 July 2018, Melbourne Law School hosted the third biennial Public Law Conference, co-organised by the University of Melbourne and the University of Cambridge. The theme of the 2018 conference was ‘The Frontiers of Public Law’. The Public Law series is the pre-eminent regular forum for the discussion of public law matters in the common law world. The first two conferences in the series were held at Cambridge in 2014 and 2016. The 2018 conference featured approximately 80 speakers, including leading judges and scholars drawn from across the common law world, and bought together over 250 delegates to discuss the most important issues in public law today. The conference series is sponsored by Hart Publishing Ltd, and we are grateful for their ongoing support.