In developing countries, the impact of the HIV epidemic has revealed the potentially devastating effects of inadequate public heath polices: disappearance of working-age adults, decrease in food resources, arrest of growth, domestic instability, monopolization of scarce resources to the detriment of other investments. The negative impact of epidemics does not only affect states, but also impinges directly on global governance. Public health is an area in which international policies will intervene massively in the coming years. Underestimating the issues involved could lead to greater world instability. This study aims to demonstrate the importance of public health for global governance and take stock of the transformations it encourages or requires at the global level. First it takes a look at the actors. The increasing role of non-government actors points up the limits of states and international organizations, and the latter two need to adjust their practices to public health issues. Second, the study examines the frameworks in which public health policies are devised, questioning the role of certain actors in defining these policies and the appropriateness of the multilateral trade framework for addressing issues of public health. In that it calls into question its modes of regulation, public health has emerged as a concern for global governance.