Traditional forms of surveillance addressed detecting outbreaks of dangerous contagious disease, case finding and contact tracing, and identifying environmental hazards. But public health today goes far beyond interpersonal contagion and environmental dangers to address patterns of ill health among the population. Increased rates of conditions such as diabetes or substance use disorders are called “epidemics” to be addressed by public health interventions including education, environmental design, economic incentives, regulation, and even prohibition. This chapter explores the ethics of this so-called “new” public health, arguing that paternalistic interference with behavior is justified only to prevent serious harm. Much information collection, however, aims not to protect individuals but to understand health or health disparities at the population level and thus is not properly regarded as paternalistic. The chapter also argues that interferences such as the requirement to wear masks in a pandemic are mistakenly perceived as protecting individuals against their own choices and are better viewed as protecting others from the possibility of harm.