Abstract Law is a tool that public health experts can use to improve population health. Generally, law offers a range of opportunities: it can encourage healthy and safe behaviours; it can change and shape the physical and social environments; influence the social determinants of health, as well as structure the public health system. Law can also compel or restrict, and legal systems can provide accountability and oversight. ‘Public health law’ stands at the intersection of public health and law, and offers a range of powerful tools for improving health (Burris et al, 2018). While public health law is an important field for public health professionals, there is a lack of knowledge about this field, and a lack of interaction between public health professionals and law professionals. There is also a need to understand the ways law might challenge public health goals. For example, law can be used to promote goals which do not improve public health, or public health concerns can be sidelined, and law can be a tool for challenging specific public health interventions. The focus of this roundtable will be on identifying and building necessary capacities for using law by public health professionals. End-goal is to identify new initiatives to consolidate and to strengthen public health law as an important field for public health professionals. To achieve these aims, we have set three practical steps for the roundtable to embark on: 1) strengthening collaboration; 2) identifying knowledge gaps and opportunities; and 3) starting new initiatives: 1) Strengthening the collaboration and building new partnerships: we bring together experts from law and public health to identify the gaps and opportunities when it comes to implementing law by public health professionals. The roundtable will foster new collaborations and partnerships between law and public health professionals. 2) Identifying gaps and opportunities: there is a need to identify deficiencies in health policy research and how to use scientific legal research methods to overcome these problems. Relatedly, to share experiences and best practices when it comes to teaching public health law. Opportunities include the transdisciplinary model and legal epidemiology; a focus on the commercial determinants; and applying a human rights lens. Panelists - in an interaction with the audience - will identify key opportunities and discuss ways to implement them. 3) Starting new initiatives: panelists will be asked to concretize existing initiatives and discuss with the audience how they can be integrated in the field, based on our new partnerships. New collaborations will be identified. This may vary from building a new network, applying for a joint research grant or for strengthening or complementing existing teaching modules. Altogether, this roundtable aims to strengthen our understanding of existing efforts and of the various ways in which public health expertise can be integrated in better law making. Key messages • Drafting of sound laws that improve health is a joint practice of various professionals, including legal and public health professionals. • We need to strengthen existing capacities and build new ones for using law by public health professionals. Speakers/Panelists Timo Clemens Maastricht University, Maastricht, Netherlands Regien Biesma UMC Utrecht, Utrecht, Netherlands Edward Kirton-Darling University of Bristol, Bristol, UK Scott Burris Temple University, Philadelphia, USA Dominique Mollet Joint Research Council EU, Ispra, Italy