Public health occupies a uniquely central place in the normative architecture of global justice. Across diverse philosophical traditions—including the capability approach, human rights theory, egalitarianism, and structural accounts of global inequality—health is consistently identified as one of the most fundamental dimensions of human well-being (Sen, 1999). The empirical distribution of public health outcomes thus provides not merely a descriptive snapshot of global living conditions but a morally charged representation of how opportunities, life prospects, and structural protections are allocated across the world. This Introduction situates public health within the broader theoretical framework of global justice and outlines the philosophical and empirical foundations that inform the assessment of this issue.