From 17 to 19 June 2020, the Faculty of Law, University of Ottawa will hold the fourth biennial Public Law Conference, co-organised by the University of Ottawa, the University of Melbourne and the University of Cambridge. The theme of the 2020 conference is ‘Public Law: Rights, Duties and Powers’. The Public Law series is the pre-eminent regular forum for the discussion of public law matters in the common law world. The first conferences in the series were held at Cambridge in 2014 and 2016, and the third in Melbourne in 2018. The 2020 conference will feature approximately 80 speakers, including leading judges and scholars drawn from across the common law world, 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.