National ethics (or bioethics) committees have been established across the globe to provide recommendations and guidance to governments and the public, thereby ensuring that public policies are informed by ethical concerns. Although the task is seemingly straightforward, implementation reveals numerous difficulties. Frequently, committees struggle with issues related to, for example, independence, funding or efficacy. Given the vital role these committees perform, it is crucial that the challenges they face and the conditions under which they can thrive are properly understood. An international, cross-sectional survey was carried out to assess the current state of national ethics committees and the problems they face. In total, representatives of 87 of 146 national ethics committees (59.6%) participated. The 84 countries covered were in all World Bank income categories and all World Health Organization regions. The survey revealed that, if the advice of national ethics committees is to matter, they must be legally mandated, independent, diverse in membership, transparent and sufficiently funded to be effective and visible. Particularly in times of great uncertainty, such as during the current coronavirus disease 2019 pandemic, governments would be well advised to base their actions not only on technical considerations but also on the ethical guidance provided by a national ethics committee. It is important that these committees are strengthened nationally and globally to enable them to provide high-quality advice on current and emerging ethical issues.