How we define and understand public health, especially in terms of our shared and individual definitions of health and the needs of multiple publics, shapes the theory and practice of public health ethics. Unfortunately, public health ethics is often reduced to a utilitarian ethic that justifies intervention or imposes behavioral modification at the infringement of personal rights and values based on the greater good, often at the detriment or upon the backs of the most vulnerable. Public health, vis-à-vis local health departments, implements evidence-based interventions with a concern for social justice to achieve health equity. Public health maintains a duty to the community to address health concerns that individuals cannot solve and that require collective action. The Catholic social and moral traditions offer unique key theological aspects that can support a new visioning of public health ethics. It is only fitting that a chapter about emerging issues in Catholic bioethics should propose a public health ethic focused on human flourishing, including a new conceptual apparatus to support public health’s mandate to promote health and prevent disease, disability, and injury in the population. This chapter will also explore how the essential services in public health can make this conceptual framework operational.