Member States of the European Union have until December 2021 to transpose the EU Whistleblower Directive into national law. Based on the latest state-of-the-art research and international best practice and standards, this policy paper offers recommendations concerning the most important aspects of implementation. This paper was written in the context of Ireland’s transposition of the Directive as a response to Ireland’s Department of Public Expenditure and Reform’s call for submissions, but has relevance for other Member States.